FIXED 2007 hhr 2.4 liter p0340

trying to help a friend out he has a p0340. have 5 volts on blue wire have low ref on tan wire. have 5 volts on signal wire plugged in and unplugged. no change. I went to the exhaust cam and checked the signal wire plugged in and unplugged has 5 volts unplugged 0 when plugged in. he put a new pigtail on it. I don't know if crossing the 5 volt ref and signal wire would cause an issue??

So the intake cam sensor signal never drops below 5V, even running? Sure sounds like a dead sensor, but I don't think you'd be posting this if it was that simple

Does the scan data register CMP signal counts? If so, you could try pulling the 5V to ground with a test light, and watch for the counts to change.

Also wondering if you could jumper the intake cam signal into the exhaust cam sensor, and make the exhaust sensor use the intake signal circuit? The PCM would be all kinds of pissed off, but it'd tell you if the wiring is OK.

If all else fails, I guess something could be wrong with the tone wheel on the cam :huh:

I gota get a connector pinout I think he has the terminals crossed between the signal and the 5 volt reference when he put a pigtail on it. but idk if thatd cause an issue. were going to swap the sensors tomorrow. and see if we get a signal from the suspect sensor on plugged in to the exhaust connector. we know it should be a pull down design. I sure would experiment jumping the signal like you said just to see what happens. guy seems bummed as heck its his baby.

you beat me to it. I wanted to swap the terminals at the pcm. but it would appear the pcm is working if its sending out the 5 volts for the sensor to pull to ground we will get it taken care of hopefully

had a bad low reference from the pcm. new pcm now have an active cam count on the scanner

cheryl hartkorn wrote: had a bad low reference from the pcm. new pcm now have an active cam count on the scanner

Wow, didn't see that coming! Looking at the diagram, both CMPs do have externally separate ground circuits at the PCM, maybe an open between the connector and the board?

I guess that explains why the signal stayed at 5V all the time, plugged in or unplugged :lol:

I was hoping it was like the Subaru I worked on recently it had a pin pushed out of the connector at the pcm barely repaired pin no pcm needed. not so lucky on the hhr though. I told him we coulda rigged it to work by adding a low reference to it from the exhaust sensor. we did and it worked but he didn't want to keep it that way.