TCS no comm. HVAC issues
Thread Starter
Safety Car
Joined: Feb 2003
Posts: 3,847
Likes: 95
From: Springfield MO
TCS no comm. HVAC issues
I've been getting the TCS codes lately on my 98. At first it was just the TCS and SES lights that were coming on. Eventually, after driving the car a few miles the lights would go off and the car drives as it should. However, the latest issue is now the HVAC does not work when the TCS and HVAC lights are illuminated. I get P01571 and p1644.
I've been doing some research and have found that my issues could be due to the ignition switch going bad. I followed Bill Curlee's post on checking the ignition switch. I followed the procedures at the bottom of this post: http://forums.corvetteforum.com/c5-t...ch-repair.html
I get battery voltage at fuses 17, 18, 19, 22, 16, and 13 under the hood. However, at the interior fuse panel I will intermediately get battery voltage at fuses 19, 21, and 22. All these checks were done with the key in the run position. I can get the HVAC to function by cycling the key off and on several times. When the HVAC does function I will then get battery voltage at the above interior fuse locations. However, when the HVAC is not functioning I do not get anything at those same fuse locations.
Does this mean the ignition switch is faulty?
I've been doing some research and have found that my issues could be due to the ignition switch going bad. I followed Bill Curlee's post on checking the ignition switch. I followed the procedures at the bottom of this post: http://forums.corvetteforum.com/c5-t...ch-repair.html
I get battery voltage at fuses 17, 18, 19, 22, 16, and 13 under the hood. However, at the interior fuse panel I will intermediately get battery voltage at fuses 19, 21, and 22. All these checks were done with the key in the run position. I can get the HVAC to function by cycling the key off and on several times. When the HVAC does function I will then get battery voltage at the above interior fuse locations. However, when the HVAC is not functioning I do not get anything at those same fuse locations.
Does this mean the ignition switch is faulty?
Thread Starter
Safety Car
Joined: Feb 2003
Posts: 3,847
Likes: 95
From: Springfield MO
Also, when the HVAC is working correctly I do not have the TCS and SES messages and no codes as well. I'm leaning towards a bad ignition switch but I would like to hear some opinions. Sorry for the long post. 
Thread Starter
Safety Car
Joined: Feb 2003
Posts: 3,847
Likes: 95
From: Springfield MO
Well, I went ahead and replaced the ignition switch. So far so good, no codes and everything seems to be functioning as normal. I'll have to wait till the weather clears up this weekend to take the car for a drive but I'm pretty sure that the new ignition switch solved my problems.
I took the old ignition switch apart per Bill Curlee's post and found 2 burnt contacts. The burnt contacts may have been the route cause of all the symptoms that I mentioned in my original post. I will report back after a drive to give a status report.
I took the old ignition switch apart per Bill Curlee's post and found 2 burnt contacts. The burnt contacts may have been the route cause of all the symptoms that I mentioned in my original post. I will report back after a drive to give a status report.
