[FIXED] 2000 Dodge Caravan, intermittent no crank with other electrical issues.

Tyler wrote: IMO, that's the high resistance in the ground circuit heating up with current flow.

Agreed. Would be a good one to try the thermal camera on.

Eric o did a video on a dodge truck with some similar issues which traced down to an ignition switch. He had locks stuttering, check engine light, no start when light would stay on but if he messed with key in switch till light went out it fired up. Would be worth a view.

Any more progress on this one, bachi?

Sorry for the long delay, I've been quite busy this week and I don't work on cars full time.

I do have some time tomorrow, and I'm planning on checking the voltages on the PCM of the wires connected to ES11 (pin 10 on C1 and pin 50 on C2 from the diagram).

I'll also ground those out just to see if the car will start.

I'll update you all on what I find tomorrow.

bachi wrote: Sorry for the long delay, I've been quite busy this week and I don't work on cars full time.

No worries! Not trying to hustle you at all, just excited to see this one fixed.

Update on this:

I've measured these voltages earlier today:

C1 pin 10 = 5.5V
C2 pin 50 = 5.5V
DLC pin 5 = 5.5V

They were all super close, probably differing by 0.01V at max

I then took a jumper and grounded pin 10 and 50, and the car starts every time, no issues at all (even the door locks don't stutter).

Considering how close the voltages are, I'm thinking ES11 is fine, but from there to the negative post of the battery there is some issue.

Now I have some questions:

1. Based on the diagrams I have seen, I'm thinking ES11 just connects directly to the battery (ie not via grounding to the body -> then from the body to battery negative) Is that what you guys think as well?

2. I'm trying to figure out where ES11 is, but my diagram conflicts with your diagram. Do you know of any diagrams I could use to pinpoint exactly where ES11 connects to the battery (or just so I don't have to tear into the harness lol)?

Thanks for the help

I then took a jumper and grounded pin 10 and 50, and the car starts every time, no issues at all (even the door locks don't stutter).

Excellent!

bachi wrote: Considering how close the voltages are, I'm thinking ES11 is fine, but from there to the negative post of the battery there is some issue.

I would agree completely.

. Based on the diagrams I have seen, I'm thinking ES11 just connects directly to the battery (ie not via grounding to the body -> then from the body to battery negative) Is that what you guys think as well?

Also agree. I don't know to a certainty, but I believe ES11 is the small cable that attaches directly to the battery cable end. I'm not looking at your van, just inferring based on Google images. :silly: I ripped this image off Google because it matches the Caravans of this vintage that I've seen in the past:





Like I said, I don't know that the small cable is ES11. Or that your van even looks like this. :silly: It just happens to neatly match the wiring diagrams.

2. I'm trying to figure out where ES11 is, but my diagram conflicts with your diagram. Do you know of any diagrams I could use to pinpoint exactly where ES11 connects to the battery (or just so I don't have to tear into the harness lol)?

Negative. :lol: I've scoured all my service info sources, and that was the best I could come up with.

Like I said, if this were my van, I'd be 100% OK with overlaying a cable with a new eyelet. Theoretically, you could just splice into the ground wires, pin #10 and #50 of the PCM, and run a new wire directly to the battery from there. It wouldn't be pretty. :silly: But it would work.

Speaking of the eyelet, it's possible the voltage drop is still closer to the battery, or at the battery itself. You could try poking the suspected ES11 cable wherever it's accessible and voltage dropping between the B- post and the cable. If you read 5.5V, you're ahead of the drop. Move closer to the battery. If you read 0V, you're behind the drop. Move closer to ES11.

Right, I should have included images of the car at some point, but yes those images are spot on, exactly the car I'm working on (including the wire that runs parallel to the main cable).

Thanks for the suggestion, I'll try poking at the wire and measuring voltage along it starting from the post to see if I can figure out where exactly the drop is coming from.

And yep you are right, I could in theory just run a direct wire from pin 10 and 50 to battery negative, although the caravan is actually my uncle's car (I'm just working on it) and I'm not sure if he would approve lol

I'll give an update on what I do as a resolution.

So ... I've figured out the issue

Attached to the b post of the battery are the main cable and the ES11 ground wire.

The ES11 ground wire has 3 parts:

The eyelet, which connects to the main cable end
The eyelet clamp, which grasps onto the exposed part of the wire, connecting the wire to the eyelet itself
and the actual ES11 ground wire

When measuring voltage from the exposed part of the wire at the eyelet clamp to the b post of the battery, sure enough ... there was 5.5V.

I cleaned it up thoroughly, retested, 0V, car starts fine.

It looks deceivingly ok, and all of the tests I did before where I attempted to move the eyelet didn't change the voltage (because I had the negative cable on tight), but it was always right there.

You are right Tyler ... the drop was pretty close to the battery

Either way, thanks for all your wisdom Tyler, you are the greatest

And thanks to everyone else who contributed to this thread

bachi wrote: When measuring voltage from the exposed part of the wire at the eyelet clamp to the b post of the battery, sure enough ... there was 5.5V.

I cleaned it up thoroughly, retested, 0V, car starts fine.

NICE.

Either way, thanks for all your wisdom Tyler, you are the greatest

And thanks to everyone else who contributed to this thread

You're the greatest for staying with it! Do you know how many techs would have thrown a PCM (or three) at this thing? This van was just begging to get hit with the parts cannon.