Hey,

I have a 1999 Blazer with the original tacho not moving at all, it just rests at zero. The SES light came on a day after the tacho stopped.

I bought a cheap code readerwhichdisplayed only one code; P0108, I checkedthe MAP sensorand some nasty creature had bitten through the wires! I fixed that and cleared the code.

After reading a number of posts I understand the CMP sensorsends out the tach signal, if this was the problem I would expect to be reading a code? Does the CMP sensor always give a code out if there is a problem?

As there aren't any codes would there be another issue not related to the actual CMP sensor?

Any help will be appreciated,

Thanks!

Adam

 

A faulty CMP sensor would trigger a code as it is crucial to the operation of the motor. It is possible that the cluster is bad.

 

Yeah, I wondered about that too.

Thanks for the reply