Weird VSS/check engine light issue
09-17-2011, 12:38 PM
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Weird VSS/check engine light issue
A few weeks ago, my speedo went dead and I checked my CEL code and got 1231, Vehicle speed sensor. It made sense, so I changed it out for an old one I had laying around and everything was fine. A couple days ago I began to get random check engine lights for the same code, but my speedo is still working fine. I replaced the sensor again, but still have the problem.
The thing is that I only get the light when I'm in gear and slowing down, usually on the highway coming down from speeds above 40 mph. Any idea what could be causing the problem? Maybe dead/low gear oil? The magnetic sensor ring in the trans? I'm just lost at this point.
The thing is that I only get the light when I'm in gear and slowing down, usually on the highway coming down from speeds above 40 mph. Any idea what could be causing the problem? Maybe dead/low gear oil? The magnetic sensor ring in the trans? I'm just lost at this point.
09-17-2011, 03:59 PM
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I'm thinking that the harness that connects your gauge cluster to the ECM might be loose or faulty.
Specifically, you're looking for the "B" plug that's fastened to the back of the gauges. Pin #9 of that "B" plug is the pin that piggy-backs the VSS signal at the Speedometer and pushes it to the ECM, where the on-board diagnostics are performed.
It goes VSS ===> Speedometer ===> ECM ===> Check Engine Light.
Most likely, the plug in the back of your gauge cluster is just loose, or needs to be cleaned.
Specifically, you're looking for the "B" plug that's fastened to the back of the gauges. Pin #9 of that "B" plug is the pin that piggy-backs the VSS signal at the Speedometer and pushes it to the ECM, where the on-board diagnostics are performed.
It goes VSS ===> Speedometer ===> ECM ===> Check Engine Light.
Most likely, the plug in the back of your gauge cluster is just loose, or needs to be cleaned.
Last edited by Loudgoldwing; 09-17-2011 at 04:05 PM.
09-17-2011, 04:31 PM
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Good idea. I did have the cluster out not that long ago to replace the odometer gear so that could definitely be it. Will check first thing in the morning.
btw sick cabbie. I like what you did with the foglights.
btw sick cabbie. I like what you did with the foglights.
09-26-2011, 04:41 PM
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this is becoming a little unsafe. The engine is dying out when I slow down almost to a stop. The sensor is somehow giving a bad read, causing both the light and the engine cut out. I've already replaced the vss. I also reset the computer and gauge cluster and cleaned all the connections. After I did that, everything was fine for almost 2 weeks.
I have a couple of theories:
1. the wires coming from the sensor itself are cracked, melted or seperated.
2. The magnetic sensor ring inside the trans is covered in metal shavings or broken, causing a poor signal.
3. The computer is dead
The check engine light only comes on when the car is slowing down. I'm gonna continue looking into the issue, but I need to fix this.
I have a couple of theories:
1. the wires coming from the sensor itself are cracked, melted or seperated.
2. The magnetic sensor ring inside the trans is covered in metal shavings or broken, causing a poor signal.
3. The computer is dead
The check engine light only comes on when the car is slowing down. I'm gonna continue looking into the issue, but I need to fix this.
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