Got a jump start... now my gauges die and my radio shuts off and...

**bobc455** · 01-19-2015

Actually it points to a subwoofer amp which wasn't powering down with the radio when it's supposed to, combined with a 5-year battery that was 8 years old, but thanks for the advice. The amp has been disconnected until I address it.

But I will remove the fuses and visually inspect them- I checked them with a low-current continuity checker in my multimeter which would not have caused a thermal situation like you describe.

**bobc455** · 01-19-2015

Is there a place where I can learn more about the CANBUS system- how it works, what devices are on it, how it communicates, etc.?

**bobc455** · 01-20-2015

For anyone interested - I found an interesting summary of the CAN bus system.

http://www.aa1car.com/library/can_systems.htm

Seems like this is where I gotta look for an issue.

Thanks,

-Bob C.

**Scottydoggs** · 01-20-2015

as far as i thought the can bus was in the pcm. so maybe try another pcm?

**bobc455** · 01-20-2015

Okay, I can do that. I have a spare PCM I can program (I think I backed up my existing PCM already, so hopefully I can give the new PCM uncorrupted data).

For some reason I thought these things had a separate body control module (which, I would then ASSume runs the can bus) - but if it does I can't find it.

Thanks, I will report back.

-Bob C.

**bobc455** · 02-02-2015

Just wanted to give a final update, in case anybody has a similar problem in the future.

1) The initial dead battery was because my subwoofer amp wasn't shutting down properly (cooling fan was running 24/7), and because my remote starter was staying active. Both issues have been corrected.
2) The other issues were because of the CANbus system. I have an aftermarket stereo. I didn't bother to post about this because I didn't think it was relevant- however, the jumpstart fiasco fried the CANbus connection to the car stereo to the point where this eventually took down the entire CANbus network. This was solved by disconnecting the battery for 15+ minutes (in my case 35), and replacing the CANbus connection to the car stereo. Crutchfield was very generous and replaced this free of charge. (In case it matters, it was the GMOS-01 device by Metra, with the AXXCESS label. Crutchfield has stated that these are actually very reliable units., but I'm on my 3rd now.)
3) While I was waiting for the new GMOS-01, I had to remove my stereo (and the GMOS-01) and the car ran fine. As stated by industrialfish, the process is to find the bad node on the network and remove it. Unfortunately, finding the bad device is very difficult except by trial-and-error, and in my case I was lucky because it was the one place I was familiar with on the network.

My next OBDII scanner will also have CANbus scanning capability!

Thanks everyone for your help.

-BC

**ADrugDealer** · 02-02-2015

Bob,

You are wrong and right. Your issue is the CAN bus; however, you have successfully placed a bandaid over the problem. The issue here is your Axxcess adapter. I have the same problem. In short the CAN Bus will look for the factory radio to get information like date/time and whatever else it needs from the radio. In the harness there is a dataline. The Axxcess only uses this for powering on the radio from what I can tell (I have a GMOS-04 and have tried multiple of them) where the car wants a reply back on this line when it asks for data. The aftermarket radio/adapter doesn't reply and the entire CAN system goes down with the exact issues in your post.

There are two "suspected" fixes.
1) Install a 5 Button DIC.. According to the TSBs I was reading the 5button takes over for the Radio where the 3 button doesnt.
2) Install the factory radio in the trunk with power ground and data lines.

**bobc455** · 02-02-2015

Fascinating. So essentially what you are saying is that Metra put out a product which was not properly designed. I guess from the car's perspective, it is driving with no radio whatsoever.

That explains why the DIC doesn't display time any more - only dashes. And it might also explain why I get about two minutes of chiming sometimes when I start the car- something in the CANbus system isn't happy.

Unfortunately I don't have the factory radio- when I purchased the car it had a different aftermarket stereo. I think it had a Schosche (spelling?) adapter at the time, but that's gone now too.

The system seems to be stable with the new Axxcess unit installed.

I have avoided the 5-button DIC because of the odometer deal, but maybe it's time for me to consider that.

I remember reading in the owner's manual that the radio verifies the car VIN before it will operate.

Thanks for the great insight!

-Bob C.

**ADrugDealer** · 02-02-2015

No problem. I have done lots of research and work with the system in the 04s, it's weird. thats for sure. You will have the problem again give it time. Look into a factory radio or 5btn

**bobc455** · 02-02-2015

I have a factory radio from a 2004, but it's from a different car so the VIN won't match. Will that be a problem, or will it still do the job?

**ADrugDealer** · 02-02-2015

That one I do not know. I would think it would work.. plug it in and see if it works lol

**bobc455** · 02-02-2015

What about switching to a different unit like the Scosche or this http://www.crutchfield.com/p_541RP5G...e.html?tp=3486 ?

Hmm. Interesting. I posted a link to crutchfield and the forum changed it to a walmart link. Holy mackerel. I was trying to link to the PAC RP5-GM11 at crutchfield's website.

-BC