Originally Posted by
kingdavid54
Short answer yes, RCM communicates with the PCM/Bcm via the can buse but, has also been known to be caused by a faulty brake light switch or a bad connection at the brake light switch which is mounted on the brake pedal arm under the dash. Other causes also but less common. Another common cause of a lot of the ailments of this cars electrical system is poor or bad ground connections, you should inspect disassemble clean with a wire brush reassemble with Dielectric grease all the ground connections under the hood including the one right at the secondary air injection pump, they may look clean but because they are dissimilar metals oftentimes they create a film of oxidation between them, when you add all of the connections together they create a lot of resistance that is not supposed to be there which in turn increases the Load on the electronic components which causes them to overheat and prematurely fail. We have several electronic engineers on this forum who can better guide you then me, they may chime in and offer some additional advice. Hope this helps
This is very helpful, thank you very much! Are there any guides with pictures for where the grounds are located? I searched but didn't turn much up. I'd be more than happy to inspect each one but I'm not really sure what to look for or where I should be looking. I'm going to take another look at the RCM - I suspect that even though the solder looked OK at first glance, it might not hurt to go ahead and touch up all of the connections that look even a little questionable. I just hope that I didn't damage anything on the RCM when I pulled it out last time; I was worried I might have scratched some traces or something on the board.
Any additional input is greatly appreciated - I love this forum!