Could this be root cause? solved but some new codes-need hose identified

Hey Sopey52! FYI, I merged the ground location thread into your original thread. Not trying to kill the conversation, but having multiple threads about the same issue/vehicle/repair makes it more difficult for anyone else to follow along.

Let me catch up with what you've posted so far.

I tried to watch the YouTube videos you posted early on, but they all show as private?

Doesn't really matter, 'cause I think you should stay on this path:

I do have fuel pump that wants to turn off and on and off and on when the van is not running when the key is in run.

That's a perceptible symptom that can we can use to get some good direction. It's also conveniently testable from the underhood fuse box.

With the off/on symptom present, pull the fuel pump relay slightly out of it's socket. Not enough to disconnect the relay from the fuse box, just enough to get to the relay terminals with your multimeter.



Take voltage readings at all four terminals, long enough to witness at least one off/on cycle. Take note of the readings and report back. At least one is going to be changing. Use the relay diagram on the top or bottom of the relay itself to tell you which terminal is which. Do not use a test light.

If getting to the relay terminals isn't possible, you can use the old trick of removing the relay and tying individual copper wire strands around each of the relay terminals before reinstalling. Just make darn sure not to let the strands touch each other or anything metal.

There are also kits like this that make relay testing a breeze:

www.amazon.com/Lisle-56810-Relay-Test-Jumper/dp/B002MCX6LY/

Sopey52 wrote: This Chevy venture has error codes that I will attach and it has evidence of patchwork done by previous owner within the wire loom.

Those four codes are all 5 volt reference related. It's possible they've been set by testing so first thing I'd do is clear them out and see if they come back.

SI for P0122 and P0452 says if P1635 is also set troubleshoot it. Found this "diagnostic aid" for P1635/9.

If any sensor using a 5-volt bias voltage, such as the intake air temperature (IAT) sensor or fuel level sensor, is shorted to voltage, DTC P1635 may set in addition to DTC P1639.

This might be a rabbit hole but it'd be worth checking the 5V and low reference circuits.

Possibly Solved....I need help identifying 2 breakers under passenger side of dash. When I flipped them after my test drive one of them was pretty hot. I think this could be involved in a 5v issue if they aren't plugged in correctly. Years ago, after the "electrical expert" had it, the module these two breakers was plugged into was hanging and I plugged it into the clips that hold the module in place. I also put black tape around the relays to keep them from coming loose. However, I never took them out and flipped them around until the other day and then I put them back the way they were because I figured I didn't solve the problem. Today I flipped them and my gauges did not go nuts since and I don't hear any fuel pump and relays and injectors flipping out while the key is in run. They did when I was shutting off before I flipped them.

I cleaned up and made grounds better through all of this but I do not think the grounds were my problem. I think my original problem its related to this. Thank you to everyone who has responded to my posts to help me think this through and not give up even though I was ready to throw in the towel.

I didn't realize that changing the subject in a reply, makes it a new thread. I thought I was just making a subject of my reply to the original thread.

So yesterday, DRY DAY, I made great progress and was able to drive the van for 12 miles but it did shut off a few times and I thought I tackled that with those two relay modules under the right corner dash because it seemed to make the guages stop acting up.

WELL TODAY IS A WET SOGGY DAY. I decided to start the van. I started right up on first key turn. I decided to let it sit and idle. That lasted about 5 minutes and it shut of. I did not see the message center "battery/low fuel/security" but the fuel pump was acting up. I started it again. I decided to take it for a ride. I went a bit further than I should have and it stalled out at least 4 times where I thought I might end up having to tow it. Same behavior as always for at least 10 years....won't crank, will crank, won't start, won't crank. Move the gear shift...won't crank, started in neutral...drove about 50 feet and stalled, got it turned aropund....got it back home with stalling and coasting....started in neutral....hard shifting some times.

Should I be using wet weather as a clue? I think made improvements but root cause of problem still remains. I also suspect I have a slightly greasy serpentine belt from changing power steering pump and accidentally spilling a bit of fluid. I also know I may have added to the problems by pulling a power stearing pump from a junk yard but I didn't want to put $140 into a new pump if this is going to go to the junk yard. The pump whines but it is gradually getting quieter.


I am really tired of revisiting those same grounds but I really made them as best as they could be. I think I have to get underneath and look for things to clean up. Wet weather has to be considered a clue as to the way it acted today because yesterday once I got it running, even if it stalled, it cranked right up with barely turning the key.

I will have to refrain from bugging you guys unless I can ask specific questions. For now I would really appreciate it if anyone can tell me what those two modules are under right corner of dash as shown behind the BCM in that previous video. I do not know if it matters how those relays are in (what is upside down or not)because only four of the 5 pins are being used. There are only 4 contacts for each of those 2 relays. Also, it is possible to plug both of those relays into the module and one could think they are properly plugged in the contacts could be completely missed plugging the relays into slots without contacts.

THIS IS IMPORTANT. Sometimes, when I start the van, the guages work. Sometimes when I start the van the fuel and temp stays floored. Sometimes the gear you are in does not light up. When I am able to start the van and all the guages work...I can drive it much further than when the guages arenm't acting correctly. Now the darn gauges sometimes don't work but the BATTERY/LOW FUEL/SECURITY, isn't happening.

First off, thanks to Chad and Tyler for taking time to read and offer advice. Tyler, I want to get to the testing you describe but I think I need to buy a new multimeter. Also, I have spotted some issues I need to consider first.I managed to keep van running long enough to get the front right wheel up on 3 2x8s so that I can get a look at starter and the junction box under van behind driver seat where there is a module that accepts 3 plugs. 1 plug goes to fuel tank. 1 plug splits to fuel and then to rear brake (I assume its abs sensor) another plub has a single light green wire (possibly security, possibly ground that goes into the conduit that contains the one that split.1. The receptacle box looks fine. However, two clips or pins inside one of the plugs are pushed in and I cannot get the plug back into the receptacle without those 2 pins pushing in. I suspect this to be possibly part of the problem.2. This may also be a big part of the problem. I finally got to where I could get a look at the starter and the connections to it. It all rusty, corroded and green.I need to resolve these two issues before I go any further.

@Tyler
I am a bit intimidated by the fuel pump relay test you described. You said it was simple. I refrained from doing it until I just now bought another mutimeter because I think the one I have has issues. However, it does not seem simple. I need to ask, is this just to verify that the fuel pump relay is good? I replaced it with another one and it does the same thing. Honestly, i am a bit stupid on some things until I physically experience doing it at least one time. Also, I corrected permissions on my videos so that the ones I shared here show up here. I had marked them private for a while because I feel defeated and stupid.

Some of what I have done so far, I did not follow a step by step procedure that a mechanic may have followed due to weather and van being outside and I did not have a jack or did not have certain tools, etc or I was waiting for a part or tool to arrive and meanwhile decided to test some other things because I had time to do it.

So far I have gone in a circle. I had a day where I got the van to run and I drove it for 12 miles thinking I had it fixed and the darn thing stalled on a back road curve with the battery/low fuel/security happening and it was a dangerous situation where I was lucky to get it started, get it out of that location and drive it home stalling 4 times on the way.

Here is what I "think"..I don't want to say I know. Consistientlly there is the P0122 TPS low circuit a. and there si the P0452 fuel pressure low voltage. I am wondering if this is a separate issue from the security system shutting me down or I am imagining that the security system shuts me down. I have revisisted ground 113 and ground 111 and ground 117 several times. I am certain the ground 113 and ground 111 are the same location. I wonder why there needs to be an earth strap from ground 117 to the body ground on the left side of the vehicle when ground 117 is only about 4 inches away grom ground 113 that the battery negative is connected to.

Also, I replaced the power stearing pump during all of this because it was leaking. I replaced the cam position sensor because it was under the power stearing pump so I figured just do it. I replaced the starter because it was a rusty bolt and wire mess on the positive connections...I replaced the oil pressure switch because I could and I believe it looked like it was leaing....still no change HOWEVER, I suspect that every time I have the battery disconnected for a long time (more than one day) I end up having to put the vehicle through a relearn process because on that day that I was able to actually move the van and take a 12 mile trip I did what i thought to be a idle relearn process with the van connected to a jump via another vehicle after going through the entire key relearn process while connected to that jump. i only did this because I met a mechanic where I pulled the power stearing pump and told him of my ordeal and he told me that the relearn process a GM dealer might end up doing because maybe I screwed up my computer with a jump (had negative cable connected to battery instead of engine) or because battery was disconnected so long....he told me it takes a lot of power for relearn and he does his with a jump connected. Some of this may sound stupid or silly to you because you are a pro..but I am just telling you what I have done so far and well....I still can't get it to run for more than maybe 3 minutes right now and then I can't start it at all until I let it sit. When I did get it running for that 12 mile trip I tested the alternator with lights on, radio on, and Air Conditioning on and it read 14.59 volts on my multimeter. Also, I have observed a couple of pins inside the PCM harness that are not out to the edge as far as they should be and the rest are but I can't get inside the back of them to adjust them or I don't know how. Also, there is a set of 3 plugs under the van behind the driver seat where 2 plugs go over the fuel tank to pump and I believe pressure sensor and then one of them splits to where I believe may be the rear ABS sensor or maybe something with fuel pressure above that rear wheel because the gas tanks cap is above that wheel. One of those plugs has 2 pins that will not stay at the end of the plug and are getting pushed back when the plug is plugged in. Hopefully this all makes sense and does not read like rambling. Thanks for your time.

I just want to let everyone know that I thought it was a good idea to make youtube videos but I marked them private for a while because 1. someone is posting strange looking links in my comments and those links go to what looks like under age porn. I reported it to youtube and they do nothing about it. 2. I kind of sound mean or cocky (because I am frustrated with this) and most of all I am pretty stupid and or making videos is not as easy as one would think once you push record. I sometimes end up saying the wrong words like "breaker" instead of "relay". I made those video links work again by marking them unlisted. Please ignore the links that someone is posting in my comments. I cannot delete them and reporting them does nothing.

I feel that I need to crack open the PCM before I do anything else and try to do a video showing the two pins (inside one of the plugs not on the PCM) that I see are pushed back. I think one of them may actually be pin 1&2 that If I understand correctly is ground on this attachement. I feel like I need to correct those pins but I do not know how to get in to do that correctly without screwing up other pins. I am not sure pins are the correct term. If I remember correctly they are inside the clear terminal plug as there is a big terminal plug that is clear and one that is blue.

If those pins are pushed in, they are probably not making contact and will cause problems. Whether they are related to your running issues will be determined by which circuit those pins are for.

Have you checked all of your power and grounds at the PCM?

A bad ignition switch can also cause a vehicle to stall. You need to check power and grounds going to and from this switch as well.

You have to be systematic when tackling this problem. Look at scan data and if there are trouble codes, could they relate to your starting and stay running problem? Look at wiring diagrams to see if any of the codes could affect your symptoms.

When it dies is it dying like power is shut off or more like a fuel problem?

Study voltage drop testing in Paul's book and elsewhere and do these tests on all of the power and grounds related to the starter system.

How old is your starter? You could have some internal electrical problems with it that could prevent the vehicle from starting.

Remember to do all of the voltage drop testing with the circuit loaded which means key on, engine off.

Do some studying on relay circuit testing. Paul has info on that in his book and on YT.

I have visited every ground in this van except for any at the very rear. I have vistited the main grounds in the engine cabin several times. I do not believe it is grounds anymore. I have replaced the starter. It is not an expensive GM. It is a much cheaper new aftermarket starter I picked up on Verizon for under $50. It looks identical to the starter I pulled. Results have not changed.I am ready to give up once again. I BELIEVE IT IS THE SECURITY SYSTEM SHUTTING OFF MY VAN.Can anyone please help me identify these two relay modules?

Have you tested the power and grounds to and from the ignition switch? A bad one can cause intermittent start and dying problems.

Transmission range switch can also cause these problems.

At this point I highly doubt it's any of those grounds that you have continually messed with. You probably need to go away from that and focus on doing some testing at the components I mentioned. You need a good wiring diagram of the starting system.

@70Monte ....Funny you mentioned Transmission Range Sensor. I had to deal with that on our Focus this week. So I was wondering if I could have an issue there...however I can read that many sensors can cause my issues I am experiencing with this van. On the Focus, I just cleaned it up and reseated it and so far so good. It may have been banged up a bit from fender bender, included a cv axel break, a year ago and there was sludge all over it.

UPDATE UPDATE UPDATE.....I managed to get rid of 1/2 of the codes and still have the P0122 Throttle positions sensor low voltage and the P0452 fuel pressure circuit low. I also found a way to get my security light to stop being part of the rotating Battery Security Low Fuel by pulling the PCM Program fuse and moving the key to the accessory position and then plug that fuse back in. It was just something I decided to try on a hunch because the manual says to pull that fuse with key in accessory to customize settings which include the alarm and or disarming the alarm. So then all I see is battery low fuel battery low fuel...I can get the van to start but it only runs for a couple of minutes and then shuts off. Then it is difficult to start but then shuts off. Eventually the Security light comes back to that sequence but does not stick around. It eventually goes away until I can finally get the van to start and run a bit and if it stalls Security is there with Battery and low fuel until I turn the key off..but then if I put it to run I only see battery / low fuel/battery/low fuel. So now Security only shows up after the van shuts off instead of being there all the time.

GROUND WIRE DISCOVERY....as far as G117, G113....I visited a Pontiac Montana and noted how those wires were compared to my van and I made mine identical WHICH INCLUDES that the earth strap from block to body I had replaced with a heavy duty ground wire is not even present on the montana...thus someone (previous owner) added that earth strap from G117 to body ground on my van. I removed it for now. Nothing has changed except that I did get rid of those PCM 5v type codes.

I need to find where G103 and G104 is located on my van because I seen a chart that says those ground locations are fuel relay and fuel pump related. I cannot find them on any chart anywhere. Can anyone access any information as to where these ground locations are at on a 2003 Chevy Venture Warner Bros edition?

I don't even know if there is a G103 and G104 on this van. If there is one I cannot find it. I want to stop playing with grounds but I keep coming back to them and especially after an experience I just had with my wife's Jeep where it would not start and absolutely nothing, including the electric locks would work. She had someone try to jump it before I got there and they must have had a bad jump cable. First i tested the battery and it read 12.59 volts. It should have hit me but it did not hit me until later. I was able to jump it because I had a good jump cable. I could have simply taken my battery negative to body ground on the jeep and realized the problem...the battery to body ground on the jeep was bad.

This is not the problem with my Chevy Venture HOWEVER, It leads me to realize that I neglected to check the entire battery negative cable because it is burried inside conduit and runs down deep and along the bottom of radiator area to the block on the right side of the starter. Both ends seem fine but.....my van will only achieve spark when a jump from another vehicle is connected. THERE IS A LONG STORY HERE as to all the things I have done in the past 2 weeks. I will need to make another video....today I got the van to run for 10 minutes and was going to drive it but.....it overheated....and for some reason it will move but not fully in gear and very rough shifting like very hard shifting because I am stuck in fast idle....I decided to replace the TPS....I need to make a video and explain it all better as I am not a good book writer.

I have done a lot of testing without commenting on this forum (believe it or not) and I am now convinced that my problem is a bad computer. Meanwhile my coolant fans and my heater blower fans will not work. I have verified that the fans work by powering them from the main plug that splits between them and I can make one fan run slow and high from coolant fan 1 and coolant fan 2 relay. I spotted that the main diode fuse in the underhood fuse box was half way out...I test it for ohm and get resistance. Its the dark black fuse with arrow on it and I can't see through it to see if it is shorted.

So far I can now get the van to run until the engine starts to overheat and I either shut it off or it shuts itself off. The battery / security / low fuel never goes away.
I found a video on youtube where a young guy solved the exact same problem with battery/security/low fuel (Buick Rondevous) by going to a junk yard and pulling the PCM, BCM and Passkey 3 module. He put it in his vehicle and all he had to do was the 30 minute key relearn and his problems were solved. Before seeing this I actually pulled everything but the PCM from a Venture. I went back 2 days later to get the PCM and the van was gone and crushed. I could have bought the PCM for $21 if I had known this.

I thank those of you who have tried to help me. I watched enough of Scanner Danner videos and did enough of my own testing to believe this is a bad computer issue.

I have also called and talked to 2 Dealerships. Nobody on this forum and even those two Dealerships cannot tell me what the two relays are that I asked about on here. I am betting they have something to do with antitheft. Meanwhile the dealerships listened to my saga and believe I either have a bad computer or it needs to be reprogrammed. I like the idea of going to a junk yard and spending maybe $70 to pull the PCM, BCM and Passkey 3 + there is one more module under right side of dash. IF I try this and fail, I give up.

That's a one way diode not a fuse (dark black fuse with arrow) fyi

I believe I have my problem solved. I know that is a diode, I called it a fuse but then again I am not a mechanic.

Anyhow, thanks for all the help. Thanks for the videos on YouTube...I have a couple of questions if you want to watch the video.
Is it possible the codes are from original vehicle that the computer was in and they just need to clear? Code reader doesn't seem
to be able to clear them.

QUESTIONS NOT INCLUDED IN THIS VIDEO: I believe my codes are because the computer is from a Pontiac Montana and is looking for an emissions air injection system that does not exist on my van. Codes are, P0412, P0418. I found a video about this regarding an Oldsmobile Sillouette and I see nothing like that on my van. Will this cause me any problems with inspection? Can I just ignore the codes and my local mechanic will know what's going on when he does the inspection? The van runs pretty darn good right now compared to what I had.

Moderator can close this because the original problem is solved. My van starts and runs and the security and low fuel light never comes on again and all of my gauges are working properly. However, I have some new codes that I am not sure about as far as are they old codes in the computer from the van at the salvage yard I took it from or do I have new codes that my old computer wasn't translating correctly because it was screwed up.

I have a P0302 that I can believe to be true. I changed that plug and I believe I need to change the cable which I simply cleaned for now.
I have a P1810 that I hope will go away after some driving and "relearning" maybe. Otherwise I am wondering if there is a relearn procedure for syncing up a PCM with a TCM. The van runs fine but there is a hard shift from 3rd to D (overdrive) but there is not a hard shift back to 3. The transmission in my van was changed and I believe I experienced this for a while after the used transmission was put in. My transmission fluid level is fine and the fluid is still nice and pink.

ANOTHER REASON FOR ME WANTING TO KEEP THIS VAN GOING. The van has 200,410 miles on it right now. The transmission is still under 100,000 miles.

My other codes are P0412 and P0418. I didn't think the secondary air pump existed on this van but I found a couple of youtube videos that say the pump is hidden inside the front driver side fender and the relay is hidden inside the front passenger side fender. I need to check this out but weather is keeping me from wanting to do it just now as its stated that I have to pull the wheel off and remove the fender splash cover. I think I just need to open up the fender splash cover.

Conclusion: The van seems to run fine and is running even smoother the more that I drive it. I have a flashing check engine light that I can't seem to get to go away. It took me a while to even be able to erase it. The codes come back and I need to resolve them. I do not believe that I need to take this van into a dealer to have my computer reprogrammed with my VIN because I took all related security modules with the PCM from a Pontiac Montana that has the same accessories. I wonder if some of the codes my old computer were throwing were bogus and this computer is giving me correct codes or if this computer will eventually clear itself of old codes from the other van. I do get the hestitation when pushing the accelerator as describe by what I have read about P0112 and P0118. I am sure P0302 can cause that too. I know my plugs are old but everyone I went to was afraid to change them or did not want to or took my money for 4 hours labor trying. I did plug number 2 with ease by myself yesterday. Plug 1 was done by a friend last year but he didn't want to change the rest. I think I could do them all if I wanted to rock the motor forward. I might do the rest of the front and think about the back while I get the air pump issue resolved. I hope the transmission issue will resolve itself. Maybe you can close this topic and if I come up with new issues I will open another thread. THANKS TO EVERYONE who has helped me.

What model year was the van you pulled the PCM from? P0412, P0418 and P1810 aren't shown in O.E. SI for the 2003 MY. Took a look at 2001 and all three are listed for it.