Help! 1992 lt 1 problem with asr

[tmkassin]

;helpHello, I am new to this forum and a first time vette owner. I have a problem with my 1992 ls 1. As I drive the asr light comes on, then the security light flashes and the gas mileage info goes boffo. The problem is not the ignition switch as I have bypassed the key chip with a resistor. I have unplugged the ecu and checked the plugs to see if they were corroded, they are not. There are not any codes in the computer. Any help is greatly appreciated. Thanks, Tom

 

[Schrade]

Good call checking the plugs (don't forget wires too).

For others' info, misrouted or faulty wires, or bad plugs will cause the wires to emit electro-magnetic radiation - same as a nuke blast, and this will cause faulty readings from all solid state sensors, including the ABS module, like I had last year YUP.

I would NEVER believed it myself if I hadn't read it in FSM '94. Talk about a revelation uh huh ...

Some faults won't light up a DTC. Do a CCM scan. Links somewhere here to scan and display CCM info...


Here's one link.
CCM scan
Beware of spicy language in that joint!!!


EDIT:
Just noticed your avatar says LS1. That right? Or LT1?

 

[tmkassin]

Good call checking the plugs (don't forget wires too).

For others' info, misrouted or faulty wires, or bad plugs will cause the wires to emit electro-magnetic radiation - same as a nuke blast, and this will cause faulty readings from all solid state sensors, including the ABS module, like I had last year YUP.

I would NEVER believed it myself if I hadn't read it in FSM '94. Talk about a revelation uh huh ...

Some faults won't light up a DTC. Do a CCM scan. Links somewhere here to scan and display CCM info...


Here's one link.
CCM scan
Beware of spicy language in that joint!!!


EDIT:
Just noticed your avatar says LS1. That right? Or LT1?

You are correct that should read LT1. Had a dysl...dislex..one of those moments. I have a FSM but was totally unaware of a CCM. Yes I have codes!!! 41 Loss of ECM serial data communications,53 Pass key detection circuit open or shorted to B+, 72 LCD dimming circuit open or shorted to ground. This is beginning to look like something possibly inside the dash?? Did I mention these are history codes and the problem is intermittent? Thanks

 

[gmjunkie]

This is beginning to look like something possibly inside the dash?? Did I mention these are history codes and the problem is intermittent? Thanks

Be my guess!! When it's doing it,press in on the lower left hand of the instrument cluster bezel right past the steering column!! Does things go back to normal??
If so pull the cluster and clean the plug connections and reinstall the cluster and make sure the screws are good and snug holding the cluster in the dash panel!!
PS Don't get them too tight as to crush the plastic!!

 

[Schrade]

I had the CCM H41, and 72 LCD circuit faults, and had the ignorance to not know the differences in ECM and CCM DTC's. So the diagnostic sequence took about 10 weeks, mostly photo-doc'ed here .

Sometime during the sequence, I replaced the plug wires, and the 41 and 72 'went away', but didn't clear from CCM, because battery disconnection doesn't clear them.

Only when considering an LS1 swap did I notice 'bad wires radiation note' in FSM, and also CCM codes-clearing procedure. And at the same time was when I found and repaired the bad 02, which allowed closed loop operation. Much smoother uh huh .

 

[tmkassin]

Be my guess!! When it's doing it,press in on the lower left hand of the instrument cluster bezel right past the steering column!! Does things go back to normal??
If so pull the cluster and clean the plug connections and reinstall the cluster and make sure the screws are good and snug holding the cluster in the dash panel!!
PS Don't get them too tight as to crush the plastic!!

OK today I pulled the speedo cluster and checked and cleaned the plug with radio shack $10 for an ounce cleaner and lube. Got in and drove home...nothing is different...I also removed the codes before driving it. My next step is going to be cleaning the connections at the ccm. I am not sure where that is and will have to refer to the FSM. Thanks for your help. Any other thoughts?

 

[tmkassin]

ASR problem solved...

OK today I pulled the speedo cluster and checked and cleaned the plug with radio shack $10 for an ounce cleaner and lube. Got in and drove home...nothing is different...I also removed the codes before driving it. My next step is going to be cleaning the connections at the ccm. I am not sure where that is and will have to refer to the FSM. Thanks for your help. Any other thoughts?

It looks like I finally solved this. On my way home after hours of searching for a bad connection in several places I decided to leave the lower cover off by the driver side under the dash. Well the lights started acting up as usual so I reached down and grabbed the plug for the key reader and fiddled with it. SYS and SECURITY lights went out immediately. It looks like a bad plug. I drove the car again today and no problem. The next step is going to be removing the plug and soldering the wires together. This took several days of searching. Maybe it will help someone else!!