Code Help
Melting Slicks
Joined: Oct 2004
Posts: 2,510
Likes: 4
From: Austin Texas
Here is more detail on the H42 :
42 PCM did not detect any EST signal within 84 crankshaft revolutions.
This is saying that no "Electronic Spark Timing" is being detected by the PCM.
Doe's your engine start OK, or does it just keep cranking ?
Did you install the Opti correctly with the "keyed Spline" ?
42 PCM did not detect any EST signal within 84 crankshaft revolutions.
This is saying that no "Electronic Spark Timing" is being detected by the PCM.
Doe's your engine start OK, or does it just keep cranking ?
Did you install the Opti correctly with the "keyed Spline" ?
Le Mans Master
Joined: Jul 2007
Posts: 5,043
Likes: 7
From: Tampa Florida
Le Mans Master
Joined: Jan 2006
Posts: 5,620
Likes: 206
From: Orlando FL
Does the engine run?
Have you cleared the codes, do they re-appear.
DTC 42, Mod 4 - is in 94 FSM page 6E3-A-90, for full description.
DTC 62, Mod 9 – is on page 5E2-88 Tach pulse malfunction
You must use the on board diagnostics to clear module 9. Disconnecting the battery will not do it, (but will clear mod 1 & 4). Go to each module an clear individually.
Page 8D-9 & sections will tell you how to clear codes.
There is definitely a skill level associated with using the FSM. The more you use it the better you get. When I got it I would just read thru it to see what was where and how it was structured. I still hunt for stuff as some of it is in no logical order. When I find something useful I use markers on the pages.
Have you cleared the codes, do they re-appear.
DTC 42, Mod 4 - is in 94 FSM page 6E3-A-90, for full description.
DTC 62, Mod 9 – is on page 5E2-88 Tach pulse malfunction
You must use the on board diagnostics to clear module 9. Disconnecting the battery will not do it, (but will clear mod 1 & 4). Go to each module an clear individually.
Page 8D-9 & sections will tell you how to clear codes.
There is definitely a skill level associated with using the FSM. The more you use it the better you get. When I got it I would just read thru it to see what was where and how it was structured. I still hunt for stuff as some of it is in no logical order. When I find something useful I use markers on the pages.
Thread Starter
Pro
Joined: Oct 2007
Posts: 735
Likes: 48
From: Reno NV
Car runs and drives good now that optispark and new icm installed.
Code 62 Tach pulse malfunction. My Tach is fine and works good.
It says Repair open in CKT 121 between EBTCM and connector c100 terminal "G1" . Refer to "intermittens and poor connections" in section 8a-4 to help identify a poor connection causing the open.
So where the hell is the CKT 121 EBTCm crap ?
Code 62 Tach pulse malfunction. My Tach is fine and works good.
It says Repair open in CKT 121 between EBTCM and connector c100 terminal "G1" . Refer to "intermittens and poor connections" in section 8a-4 to help identify a poor connection causing the open.
So where the hell is the CKT 121 EBTCm crap ?
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Le Mans Master
Joined: Aug 2000
Posts: 8,838
Likes: 31
From: Australia
I don't own one of those fancy late model cars but my take on it.
The fault code is in Module 9 = ABS/ASR .
NOT a fault with your tacho
There is a bad connection in the tach pulse signal to the ABS/ASR system.
The wire in question is circuit 121 which runs from the Electronic Brake Traction Control Module to pin # G1 at the C100 connector.The connector should be on a wiring loom.
Your circuit diagrams will show the colors for the 121 cable; easier to follow.Need to locate EBTCM and follow wiring
Somewhere in your FSM there is a diagram of the wiring loom connector locations and numbers.
Last edited by rodj; Jan 7, 2009 at 06:44 AM.
Le Mans Master
Joined: Feb 2000
Posts: 9,715
Likes: 27
From: Kempner Texas
Thread Starter
Pro
Joined: Oct 2007
Posts: 735
Likes: 48
From: Reno NV
Le Mans Master
Joined: Aug 2000
Posts: 8,838
Likes: 31
From: Australia
The "quick answer" is you have a problem with your wiring to the ECTBM.
Find it and fix it or puts some tape over the check engine light so you can't see it.
People like you **** me ;
I don't own a late model car but I went to the trouble of doing some research on YOUR behalf to solve YOUR problem and all we get is "I'm being dicked around."
You have the answer ; sort it.
Thread Starter
Pro
Joined: Oct 2007
Posts: 735
Likes: 48
From: Reno NV
What more can we do , come around and fix your car for you
The "quick answer" is you have a problem with your wiring to the ECTBM.
Find it and fix it or puts some tape over the check engine light so you can't see it.
People like you **** me ;
I don't own a late model car but I went to the trouble of doing some research on YOUR behalf to solve YOUR problem and all we get is "I'm being dicked around."
You have the answer ; sort it.
The "quick answer" is you have a problem with your wiring to the ECTBM.
Find it and fix it or puts some tape over the check engine light so you can't see it.
People like you **** me ;
I don't own a late model car but I went to the trouble of doing some research on YOUR behalf to solve YOUR problem and all we get is "I'm being dicked around."
You have the answer ; sort it.
Just asking for quick answer. Like buy new wiring harness to fix it or buy ebtcm fixed my problem from someone who had problem. All the wires look new I cleared the abs code and it came back. Guess I will have to take it to a shop or dealer to fix it.
Le Mans Master
Joined: Aug 2000
Posts: 8,838
Likes: 31
From: Australia
