I just went out with a flash light and check under the hood for the PCM.
I see the air box and all I can find is the EBCM which is located just behind air box.
Do I have to remove air filter entirely to see the PCM? Like open te box up?

 

It has just occurred to me that the last time I checked my cars DTCs and they came up clear was just prior to having my air filter changed. I haven't checked
For codes since then until I had my e-test.
Knowing now that is the location of the PCM I have a strong suspicion that may be my culprit.

I remember watching the know nothing kid do my air filter as he reefed back and forth on housing. Clearly he was having trouble, now I have someone to blame if I can find any issues at PCM connections

 

yeah i had to take my air filter out and it was inside. the ground wire for it is under the computer itself.

 

Question: Did you take a second reading with your scan tool after the failure? It seems odd to me that your car would run fine, and then pass on your scan tool but fail on theirs. Could it be that their scan tool, or computer, what ever they are using is giving irronious readings? I would also check with a third scan tool just to be sure. But they all should get the same readings.
With the codes that they gave you, nothing should be working, let alone, working correctly in your car! I would pay the $100 to have the dealership read it. Theirs give specifics!

 

I compared their results with my own scanner, and yes all the DTCs they pulled were now showing up on my scanner.
So the codes are still there.
But I have the same opinion as you, if these codes are present my monte shouldn't even run, but it does, it works great.

So yes it has been verified against another unit. But no we haven't used a third scanning tool yet.

My last good scan was about 4 months ago just before I brought in for an oil change and air filter replacement. It hasn't been scanned since then until they did the ETest.

For all I know these codes may have been present since that day.
But I have no way of knowing when they actually came up.
The shop that did the ETest said they were preset before they ever touched it and will not be held responsible for repairs

Does anyone know if I have to do a relearn after disconnecting BCM/ PCM etc?

 

You shouldn't have to do a relearn. My Battery was dead dead for 2 weeks cause I left my ignition in aux. I jumped it and it started fine but that may have just been my luck. I would try clearing the codes and checking the round to the PCM. It is under the air filter in the air box. Disconnect the neg batt terminal, then I think it is an 8 mm bolt that holds the 2 half's of the harness connector into the pcm. I have never pulled the PCM itself out but I have removed the harnesses. Check your ground. I would also check the harness at the OBD II connector. Something doesn't add up with those codes and the car running right!

 

Have you checked the CLSTWBCM fuse?

Edit: It is located in the driver side fuse panel on the end of the dash.

 

Yes I have checked and double checked every fuse in the car, inside and out.
Had the air box apart this afternoon and checked over my PCM. All connections looked great. I put some di electric grease on the plug.
I ohmed out the ground underneath and it was fine. I applied the DE grease to it anyway.

I also put the DE grease on BCM plugs and battery terminals.

Does anyone have a video sample of dash and gauges under normal start up conditions.
Cycle from off to ACC ON and them STart

 

i went out and turned my key and this is what happens...in ac position the only light i see is the battery light. when i click to on position my air bag light, seat belt brake, trac off, abs, check engine lights come on and the info box tells me my door is ajar since i didn't shut my door. it also says security and battery. after a few seconds the brake, air bag, seat belt, trac off and abs go away, check engine light stays on till i start the car. its still says security and battery till i start the car as well. this is a perfectly normal start up. i have no codes in my system. i hope this helps

 

oh i forgot to add...gauges do not move until after in ON position and the only one that did move was my fuel gauge. looking from left to right i have fuel, temp, speed, then rpm and thats it.