Possible PCM Problem?

[dam718]

Howdy Folks,

I have a 2005 Redline, and right now, as we speak she is sitting in my driveway purring like a kitten warming up from the frigid ass cold...

The engine runs like a top, when you hit the gas it revs up, just like it should...

About 30 seconds after I started the car this morning, (It started right up, so no cold start MECHANICAL issues), the ABS light illuminated and in the display window it read "PWR STR". I thought this was odd because yesterday on my way to work the brake light on the dash came on while driving through my neighborhood. WTF? So I shut the car off, started her back up, and everything was cool...

This morning I tried the same thing when the "PWR STR" indication came on, and the ABS light came on... I tried shutting her down and restarting and it seemed to work... For about 30 seconds...

The ABS light came on, but this time it would stay on for about 5 seconds, then turn off for 5... On for 5, off for 5... Know what I mean? And the "PWR STR" indication was doing the same thing.

After about 1 minute of the indications cycling on and off all the guages died (Including my interceptor), and the daytime running lights came on with the parking brake engaged??? WTF???

The ABS light is still on... The Brake light is on and appears to be running normally, as it turns off when I release the parking brake...

In fact, everything works fine except the gauge cluster... Could the interceptor be causing this? I HIGHLY doubt it, since it's been on there for a while with no issues at all...

Anyone seen anything crazy like this? Like I said, engine runs great, but the computer doesn't seem like it wants to play anymore...

[ptparker]

That sounds like a dead/dying BCM. The BCM controls all of your ABS, Gauges, Security, and some functions related to starting your car (among other things).

Just make sure you disconnect your interceptor before you take it in, so they don't try to pin it on you.

[crazybrew609]

yea thats a bad BCm.. it's covered don't worrie... takes about 40 mins to change them out and reprogram them... nothing to hard.. get the car into the shop ASAP tho cause when they ABS light is on it means you have no ABS anymore... which in this time of the year is not good.. take it in ASAP and the dealership will fix it for you knowing your ABS doesn't work

[dam718]

I took it in and here is what they did... Because of the passlock issues, they replaced the ignition switch... I guess many ION's have had problems with the ignition switch.

They did get a few codes... I didn't write down the code numbers (dumb me)... They were for loss of communications issues with the power steering system, ABS system, and Instrument Cluster...

I called roadside assistance this morning once my car wouldn't start and arranged for a tow, but before she dispatched the tow truck I tried starting it again and it fired right up. All systems were good to go.

They said that my Interceptor could possibly be causing the communications issues, which I do believe they are full of shit about, but they asked me to leave it disconnected for a week or two to see if the problem comes back.

So now all the codes are cleared, and the car runs great.

But my big question now is, does the Interceptor even connect to pins associated with the BCM? I don't think it does, I think it is only connected to the PCM. Blah, anyway, it's a bunch of crap if you ask me...

Think it's okay to reconnect the Interceptor?

Oh yeah, they were cool with the interceptor being there and said it wouldn't affect my warranty, but just in case it was somehow masking a real problem to not connect it. In fact, none of the service guys had ever seen an interceptor.... They obviously thought it was the coolest thing they had ever seen. Other than telling me to unplug it, they were totally cool with the interceptor and boost guage / ladder tach. Very complimentary on both...

[ptparker]

Originally Posted by dam718

I took it in and here is what they did... Because of the passlock issues, they replaced the ignition switch... I guess many ION's have had problems with the ignition switch.

They did get a few codes... I didn't write down the code numbers (dumb me)... They were for loss of communications issues with the power steering system, ABS system, and Instrument Cluster...

I called roadside assistance this morning once my car wouldn't start and arranged for a tow, but before she dispatched the tow truck I tried starting it again and it fired right up. All systems were good to go.

They said that my Interceptor could possibly be causing the communications issues, which I do believe they are full of shit about, but they asked me to leave it disconnected for a week or two to see if the problem comes back.

So now all the codes are cleared, and the car runs great.

But my big question now is, does the Interceptor even connect to pins associated with the BCM? I don't think it does, I think it is only connected to the PCM. Blah, anyway, it's a bunch of crap if you ask me...

Think it's okay to reconnect the Interceptor?

Oh yeah, they were cool with the interceptor being there and said it wouldn't affect my warranty, but just in case it was somehow masking a real problem to not connect it. In fact, none of the service guys had ever seen an interceptor.... They obviously thought it was the coolest thing they had ever seen. Other than telling me to unplug it, they were totally cool with the interceptor and boost guage / ladder tach. Very complimentary on both...

The interceptor connects to the PCM, not the BCM. The interceptor uses OBD-II to talk to the PCM. Most cars (between 1996 and today, just not new models) use OBD-II or a variation of it to talk to both modules.

Our BCMs use CAN. So as you are driving, the PCM (has speed sensors connected to it), sends the speed and rpms to the BCM (which controls the instrument panel) in the form of CAN data packets. That is just an example of the kinds of info that pass across the CAN.

The PCM can talk on both the CAN and the OBD2 network, but the BCM can only talk on the CAN network. Since the Interceptor only talks to the BCM, it is not even on the same network as the BCM