Code 43 Diagnosis Question?
Thread Starter
Drifting
Joined: Jan 2001
Posts: 1,970
Likes: 21
From: Denville NJ
Code 43 Diagnosis Question?
I'm in the process of diagnosing a code 43 condition on my '86 L98 iron head base coupe. I have the FSM and I'm up to step 5 and I show under 6 volts. The listed procedures are as follows:
o IGNITION "OFF"
o DISCONNECT ECM A-B CONNECTOR.
o IGNITION "ON"
o RECHECK VOLTAGE ON CKT 457
Here is my question. Where is CKT 457? I looked up 457 in the circuit identification table and it's listed as Yellow Black ESC Controller Half-Function Output to ECM. I can't find any such circuit
What am I missing? Could this be a misprint? Thanks for any help
o IGNITION "OFF"
o DISCONNECT ECM A-B CONNECTOR.
o IGNITION "ON"
o RECHECK VOLTAGE ON CKT 457
Here is my question. Where is CKT 457? I looked up 457 in the circuit identification table and it's listed as Yellow Black ESC Controller Half-Function Output to ECM. I can't find any such circuit
What am I missing? Could this be a misprint? Thanks for any help
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
Charles, I am looking at my 86 FSM and it shows the same as your stating. I don't see a ckt 457 either. It says recheck something that was never check. My only guess is recheck the voltage on term B7 again. It says:
Engine idle...back probe B7
under 6v
Ignition on, engine stopped
recheck B7
under 6v
Ignition off
Disconnect A-B connector
Ignition on
recheck ckt 457 (I would think this might be to recheck B7????)
Don't know what is going on there. Sorry maybe someone else has a solution.
Engine idle...back probe B7
under 6v
Ignition on, engine stopped
recheck B7
under 6v
Ignition off
Disconnect A-B connector
Ignition on
recheck ckt 457 (I would think this might be to recheck B7????)
Don't know what is going on there. Sorry maybe someone else has a solution.
Thread Starter
Drifting
Joined: Jan 2001
Posts: 1,970
Likes: 21
From: Denville NJ
Originally Posted by RRT vette
Charles, I am looking at my 86 FSM and it shows the same as your stating. I don't see a ckt 457 either. It says recheck something that was never check. My only guess is recheck the voltage on term B7 again. It says:
Engine idle...back probe B7
under 6v
Ignition on, engine stopped
recheck B7
under 6v
Ignition off
Disconnect A-B connector
Ignition on
recheck ckt 457 (I would think this might be to recheck B7????)
Don't know what is going on there. Sorry maybe someone else has a solution.
Engine idle...back probe B7
under 6v
Ignition on, engine stopped
recheck B7
under 6v
Ignition off
Disconnect A-B connector
Ignition on
recheck ckt 457 (I would think this might be to recheck B7????)
Don't know what is going on there. Sorry maybe someone else has a solution.
What has me puzzled is the fact that circuit 457 actually exists but is not illustrated anywhere that I have seen??? The only thing I can surmise is that it may have been intended to be used on the "A" terminal of the ESC Module which I believe is not used.
Le Mans Master
Joined: Oct 2003
Posts: 6,130
Likes: 2
From: seattle WA
Didn't realize the ESC circuit on an 86 was different than an 87, on an 87 it is circuit 485 and a few others....but no 457. On an 87 circuit 485 runs from the ESC terminal C to B7 on the ECM. Don't know if that helps at all.
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
Just went out and looked at the ESC module connector on my 86E. I see E-dark blue, D-brown, C-black, and B-pink/black stripe. A doesn't have a wire going to it and I see in the circuit index that ckt 457 is yellow with black stripe as you stated. Not sure what to tell you, but at least you know your not losing your marbles. 
