I am having a really odd issue with my 04 Grand Am, which shares a lot of common stuff with the Monte technology. I want to know if anyone has come across these systems with a Monte (or even a Grand Am). I have not had a chance to dig in the shop book yet, but figured I'd start making some inquires here and see what advice I can get.

As you read, let me start with, I had access to a brand new Dorman ignition switch (but I re-used my lock cylinder with the anti-theft chip in it), this did not change the issue.

Symptoms/Observations:
If I use the key, sometimes it cranks while in accessory mode (never starts) and moment I switch to on, it starts right up. This usually happens after I take the key out and put it back in. Other times, such as cycling the key from on back to off and attempt to start it with the key on the start mode, no crank, no start. If I cycle from off, to accessory to on and then to start, the radio and hvac blower well run, but when I hit start, the radio stops and the blower stops. I checked for the security light, and it is not active (which suggests it's not a security issue, but I'm not going to rule that out 100%).


I can remote start it 100% of the time and if the key is in the on position, the car continues to run as expected. I installed this about 1.5-2 years ago and it never had an issue.


Thoughts and Current Next Ideas:

If it was not for the weird fact it cranks in accessory mode and starts in the on mode, this would almost sound like an anti-theft issue stopping the car from starting.


- I plan to unplug the aftermarket remote start kit, see if something inside it's module has failed and can account for this.
- Rip the car apart and check all the wiring I had to tap into for the remote start kit (which I soldered all the connections and wrapped with electrical tape).

- I have access to another ignition lock cylinder with known good security chip (it's an aftermarket one that came with the car when I bought it, since I wanted all the keys correct, a friend at a dealership had issues re-keying the aftermarket one and got me a deal on a brand new AC Delco one which is in the car now and had been working fine). Re-test using this aftermarket assembly and see if that changes any results.


Any other thoughts? Anyone see where the car cranks in accessory mode (with two different ignition switches)?

 

My first thought is that it's the ignition lock cylinder. Maybe not the cylinder itself but the wiring in and/or around it. Barring that, I'd check the remote start next, and save tearing it apart and checking all the wiring as a last resort.

 

Thanks SupplySgt for the idea. By the time I saw this post, it looks like it *might* be a PCM.

I began some of the simple stuff. Gaining access to the remote start was no issue, so I unplugged it, no change (same problem). Dad came over and he had some tests he suggested based on the schematics in the shop book. Long story short, the only thing he could come up with is that the PCM is engaging the starter relay when it should not.
I happen to have a spare PCM that works for the Grand Am (conveniently my Grand Am and Monte use the same PCM, just different software, so I re-flashed it with the Grand Am software).
Put the PCM in, after it finished the security relearn, it cranked for a second and stopped. After all this crap, the battery is dead and my charger seems to be dead too. Tomorrow I am going to borrow a charger.
But, the plus side so far, this PCM did not attempt any unexpected cranking of the starter. Unfortunately, since it had to do a security re-learn, not sure how valid that information is yet. I hope to know more tomorrow.

 

I had a 96 cavalier that did something very similar, it was a relay up by the radiator, gm actually had a recall for them (I think, but I just changed it myself)

 

Interesting. We checked the only relay involved that we saw in the schematics that could cause this. We even traded it with a known good relay from another car. No change.

 

Very interesting Jason.
This is the first I've heard of this exact problem, I would have thought the ignition switch or remote too, but I think your on the right track. By the sounds of it the circuitry of the electronic ignition control within the PCM has a short. I'm extremely curious to know what you come up with.

Good luck!

 

Typically, in my experience, if it is a security issue then it won't even attempt to crank (this is on a 5th gen Monte though). Could still be the ignition switch, as there are wires that come from it that are brittle (again, on a 5th gen Monte). Best of luck.

 

So, I did successfully swap the PCM (finished on Wednesday after recharging the battery). The car no longer cranks when going to accessory mode. Appears to function as expected, no issues.
I took apart the old PCM, hoping MAYBE something fried/popped and left a visual, no such luck. I know that was a long shot as normally electronics don't do that, but was worth the 5 minutes.

Everything has been 100% fine until running an errand yesterday. Went to turn the ignition to start and it did everything it should ACCEPT crank the starter. Luckily, I was able to avoid being stranded, I hit the remote start on my key fob, it came to life and I was able to go. This issue I think might be ignition switch (which right now I have my original one back in the car). It only did it once, but that is enough to see there is still an issue. Maybe I had a double whammy of a problem....

Also, I might add, the security light never activated, other then the power on test.

 

It's gotta' be the the switch. Failure sometimes doesn't throw a security light. Remote starter must be bypassing the bad switch contact allowing start up. I know you know to go with ACDelco on the replacement.

 

So, now my Grand Am problem is back 100%. It cranks in accessory mode. What a mess. So now, I am not sure if the PCM was really related to the issue or if I got lucky on this one.

And Plumbob, you are right, the remote start takes the place of the switch basically. When installing it, you have to tie into wiring that goes to the switch (which I rechecked my connections to see if something was wrong, everything is still soldiered and nothing is exposed).

My only mention of the security light is that to my knowledge, if this was the anti-theft system causing a no-start, then I would assume that light would activate (and there should be a code that can be detected with the TechII).

Best we can tell, no shorted wiring. But maybe we are missing something somewhere (or it's shorting at odd moments).