Speedo problem?
Thread Starter
Racer
Joined: Nov 2004
Posts: 312
Likes: 0
From: Sacramento CA.
Speedo problem?
Yesterday wile driving my wife’s 90 vert. the speedometer failed, indicated 0 MPH. I found that if I touched the brake peddle enough to turn on the stop lights, but not enough to drag the brakes, the speedometer read correctly. The odometer also stopped counting. Has anyone else encountered this problem? All other dash functions are proper. 
Thread Starter
Racer
Joined: Nov 2004
Posts: 312
Likes: 0
From: Sacramento CA.
The same thought occurred to me Bogus, but could not figure how the brake would have an effect. I was thinking more along the lines of the cruse control circuit, maybe a switch on the brake peddle? Any one else with some ideas? 
Racer
Joined: Dec 2012
Posts: 451
Likes: 14
From: Okehampton Devon
Yesterday wile driving my wife’s 90 vert. the speedometer failed, indicated 0 MPH. I found that if I touched the brake peddle enough to turn on the stop lights, but not enough to drag the brakes, the speedometer read correctly. The odometer also stopped counting. Has anyone else encountered this problem? All other dash functions are proper.
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
The VSS (Vehicle Speed Sensor) signal goes to the ECM first and then to the dash.
The only way I can think of offhand to test that the VSS signal is getting to the ECM is if you have an automatic trans then the TCC (Torque Converter Clutch) should engage at roughly 40 MPH. The ECM will also show an error code 24 if the VSS signal is not present.
It sounds like the problem is in the cluster. I have virtually no experience with the 1990 and later cars so I can't help you there.
The only way I can think of offhand to test that the VSS signal is getting to the ECM is if you have an automatic trans then the TCC (Torque Converter Clutch) should engage at roughly 40 MPH. The ECM will also show an error code 24 if the VSS signal is not present.
It sounds like the problem is in the cluster. I have virtually no experience with the 1990 and later cars so I can't help you there.
