Codes after removing ECM
Thread Starter
Instructor
Joined: Sep 2011
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From: Colorado
Codes after removing ECM
Ugh! I had to replace the heater core in my '85 and now I have 12 codes and the Check Engine Lite. Before I pulled everything out I checked to see if there wuz anything that needed to done with the ECM and disconnected the battery. It's a little disconcerting that all this stuff happened. My question is did I miss something and the FSM didn't list have any information. I have a scanner and pulled codes and will work these out. I guess I wanna know wot happened?
Bill
PS. Wuz it the anchovies?
Bill
PS. Wuz it the anchovies?
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It may help if you could post what codes.
Thread Starter
Instructor
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From: Colorado
Codes are
12 diagnostic mode, no dist signal to ECM
13 oxy sensor
14 coolant sensor
22 TPS
25 Spark referance 24x signal (low volt) or MAT or IAT temp high
31 CAM sensor
36 MAF burn off, DIS fault loss of 24x, Ignition sys fault loss of HRP signal
41 CAM sensor, Cylendar select error, Elec Spark Timing open or shorted during running, Ignit sys fault loss of 1x reference pulse signal
42 EST open/shorted
Two I know about deal with the cruise control.
12 diagnostic mode, no dist signal to ECM
13 oxy sensor
14 coolant sensor
22 TPS
25 Spark referance 24x signal (low volt) or MAT or IAT temp high
31 CAM sensor
36 MAF burn off, DIS fault loss of 24x, Ignition sys fault loss of HRP signal
41 CAM sensor, Cylendar select error, Elec Spark Timing open or shorted during running, Ignit sys fault loss of 1x reference pulse signal
42 EST open/shorted
Two I know about deal with the cruise control.
Thread Starter
Instructor
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From: Colorado
Le Mans Master
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From: near the thumb in the mitten
With codes that are set I would double check both connectors are fully seated in ecm and/or for blown fuse first. The codes center with C-D connector which is the longer of the 2.
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From: Anaheim CA
Codes are
12 diagnostic mode, no dist signal to ECM
13 oxy sensor
14 coolant sensor
22 TPS
25 Spark referance 24x signal (low volt) or MAT or IAT temp high
31 CAM sensor
36 MAF burn off, DIS fault loss of 24x, Ignition sys fault loss of HRP signal
41 CAM sensor, Cylendar select error, Elec Spark Timing open or shorted during running, Ignit sys fault loss of 1x reference pulse signal
42 EST open/shorted
Two I know about deal with the cruise control.
12 diagnostic mode, no dist signal to ECM
13 oxy sensor
14 coolant sensor
22 TPS
25 Spark referance 24x signal (low volt) or MAT or IAT temp high
31 CAM sensor
36 MAF burn off, DIS fault loss of 24x, Ignition sys fault loss of HRP signal
41 CAM sensor, Cylendar select error, Elec Spark Timing open or shorted during running, Ignit sys fault loss of 1x reference pulse signal
42 EST open/shorted
Two I know about deal with the cruise control.
You said your car is an '85, but maybe it's a '95?
If not a '95, then you need the correct scanner data template. Reset the ECM and see how that affects the error codes.
Last edited by Cliff Harris; Feb 6, 2014 at 01:31 AM.
Thread Starter
Instructor
Joined: Sep 2011
Posts: 107
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From: Colorado
Those codes are not for an '85. First thing I saw was "CAM sensor", which an '85 doesn't have. All the cruise control functions are done by the dashboard, not the ECM.
You said your car is an '85, but maybe it's a '95?
If not a '95, then you need the correct scanner data template. Reset the ECM and see how that affects the error codes.
You said your car is an '85, but maybe it's a '95?
If not a '95, then you need the correct scanner data template. Reset the ECM and see how that affects the error codes.
I'll try resetting the ECM tomorrow thanks
Last edited by Mtn Billy; Feb 7, 2014 at 07:18 PM. Reason: more info
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are you reading the "Flash codes" ?????
and does that correspond to what your scanner says? I bet it don't...
Seeing the list of almost every eng mngt code there is tells me that its communication and not actually problems. Check the ECM harness plugs and IF the flash codes are showing ALL these, which I doubt, (would take a week to display thru that many) I'd drop the ECM and check the prom, and pins in the connectors..
and does that correspond to what your scanner says? I bet it don't...
Seeing the list of almost every eng mngt code there is tells me that its communication and not actually problems. Check the ECM harness plugs and IF the flash codes are showing ALL these, which I doubt, (would take a week to display thru that many) I'd drop the ECM and check the prom, and pins in the connectors..
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St. Jude Donor '16
Ok, so did you remove the ECM? or just the battery? Did you have any grounds off? What were the codes before you started?
Race Director
Joined: Feb 2002
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From: Compound in the Grove, Ga.
2026 Corvette of the Year Finalist - Unmodified
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St. Jude Donor '16
As suggested go back and remove and check all the ECM plugs check the pins very close and reseat. I have found over the years when something messes up after I worked on it, it was something I touched.
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You really need to disconnect and ensure the ECM connectors are fully seated.
I fought with those blue "combs" that safety the connectors.
After having many long discussions with those combs, they decided they were not necessary and flew out the window.
Haven't had a problem since they flew the coupe....