New ECM troubles...
07-18-2016, 09:30 PM
#21
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Join Date: 01-23-2009
Location: Fredericksburg, Virginia
Posts: 24,696
Do you think maybe reversing the grounds (low ref) and 5V ref could cause massive problems? Hopefully the computers and TB and acc pedal position sensor are not all blown up.
You will need to know EXACTLY what year and model your TB came from. LSJ doesn't mean anything to AllData or Mitchell, unless you're talking Duesenberg Straight 12.
You will need to know EXACTLY what year and model your TB came from. LSJ doesn't mean anything to AllData or Mitchell, unless you're talking Duesenberg Straight 12.
07-25-2016, 06:46 PM
#23
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Thread Starter
Join Date: 01-13-2016
Location: Colorado Springs, CO
Posts: 43
LSJ TB is from a 2006 cobalt SS. Main codes returned are still:
-P0315
-P0651
-P1682
I bought a scan tool and can get it to crank while I'm erasing codes, but it won't start and codes won't erase. I can hear the pumps and smell gas getting to the engine.
-P0315
-P0651
-P1682
I bought a scan tool and can get it to crank while I'm erasing codes, but it won't start and codes won't erase. I can hear the pumps and smell gas getting to the engine.
07-25-2016, 07:56 PM
#24
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Join Date: 01-23-2009
Location: Fredericksburg, Virginia
Posts: 24,696
Without looking at anything, since this is the 4th time in a week for P0651. That means a sensor is shorted out.
It is the 5V ref circuit; there are 2 of them., both go to the Acc Pedal Pos Sensor, one goes to the Throttle Pos sensor. And the MAP, refrigerant pressure sensor and the fuel tank pressure sensor
Anyway, it is a short, usually in the harness.
P0315 mean the crankshaft position sensor needs to be re learned, that takes a Tech2 or equivalent. On 2.2L and 2.4L VVT cars you have to do it if you replace the ECM.
p1682 is an electrical imbalance in the ign circuit. Basically it might be a blown fuse and it could cause the P0651. Fuse #25 on the BCM or Fuse #43 under hood maybe some others.
P1682 CHEVROLET Ignition 1 Switch Circuit 2 | AutoCodes
It is the 5V ref circuit; there are 2 of them., both go to the Acc Pedal Pos Sensor, one goes to the Throttle Pos sensor. And the MAP, refrigerant pressure sensor and the fuel tank pressure sensor
Anyway, it is a short, usually in the harness.
P0315 mean the crankshaft position sensor needs to be re learned, that takes a Tech2 or equivalent. On 2.2L and 2.4L VVT cars you have to do it if you replace the ECM.
p1682 is an electrical imbalance in the ign circuit. Basically it might be a blown fuse and it could cause the P0651. Fuse #25 on the BCM or Fuse #43 under hood maybe some others.
P1682 CHEVROLET Ignition 1 Switch Circuit 2 | AutoCodes
07-27-2016, 09:16 AM
#26
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Thread Starter
Join Date: 01-13-2016
Location: Colorado Springs, CO
Posts: 43
Hola! With some of these testing procedures on the car they ask to connect black multimeter lead to car battery black terminal. Battery is in trunk and I can't reach it with multimeter. Where else can I attach black multimeter lead on the car to test 5 volt reference?
07-27-2016, 09:34 AM
#27
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Join Date: 01-23-2009
Location: Fredericksburg, Virginia
Posts: 24,696
Any chassis ground should work. The most correct is the marked nut on the driver side strut tower. Any of the ground locations listed in https://www.chevyhhr.net/forums/how-...cations-56504/
Since your problems seem to be with the TPS, I would start looking at the 5V ref there.
Since your problems seem to be with the TPS, I would start looking at the 5V ref there.
Last edited by donbrew; 07-27-2016 at 10:14 AM.
08-01-2016, 06:45 PM
#30
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Thread Starter
Join Date: 01-13-2016
Location: Colorado Springs, CO
Posts: 43
FINALLLLY!!!! Turned out to be a 3 part problem.1- the original mechanic had the wrong plug in the TB harness. similar connectors but not the right pinouts. we noticed from the color differences on the wires.
2- the TB adapter still wasn't wired correctly (fixed that previously). should be from 2007 hhr to 2006 cobalt lsj sc tb.
3- the ecm harness wiring checked out fine, but WHEN PLUGGED IN the wires on some connectors backed out just a hair and didn't make firm contact. We backprobed the troubled wires, pushed them back while doing so, and found the issue.
Everything works now, just waiting for the new ECM to come back from testing. GREAT HELP donbrew I applaud you.
