just change the speedometer sensor on my allison because speedometer stop working ,moving at 1oo kms needle went down slowly to 0 always appen when hot moving for 1 hours or more????
just change the speedometer sensor on my allison because speedometer stop working ,moving at 1oo kms needle went down slowly to 0 always appen when hot moving for 1 hours or more????
A Tech II Scan Tool can be used to evaluate vehicle speed. This can be used to determine whether the dash speedometer is the problem.
Jim
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You can also check vehicle speed sensor output with a Predator programmer. If the value matches the speedometer, it's the sensor. If it doesn't match, it's the speedo (replace/repair the IPC). Often, you can fix a lot of IPC errors with a computer reset. Disconnect BOTH battery + cables and ground a cable to the chassis for at least 30 minutes. Be sure BOTH batt+ terminals are NOT connected to anything.
Another, perhaps less expensive, option would be to acquire a salvage IPC. I bought one for my D/A/ conversion for not a lot.
Jim