The speed is the only section of the cluster that doesn't work? This is the procedure to test it.
Speedometer Inoperative 1. Unplug Vehicle Speed Sensor (VSS) buffer. On Commercial Van, VSS buffer is located on shipping panel, to left of steering column. On Van, VSS buffer is located on parking brake bracket. Turn ignition on. Check for battery voltage between Pink/Black or Pink/White wire and ground. If battery voltage does not exist, check for open or short in Pink/Black wire or Pink/White wire. 2. If battery voltage exists, check for voltage between Pink/Black or Pink/White and Black/White or Black wires. If battery voltage does not exist, check for open or short in Black/White or Black wire. If voltage is okay, raise and support vehicle. Leave VSS buffer unconnected. Start engine. Shift transmission into gear. 3. Check for AC voltage that varies with engine RPM between Purple/White and Light Green/Black wires of VSS buffer connector. If AC voltage does not exist, check for open in Purple/White or Light Green/Black wires. If wires are okay, replace vehicle speed sensor. If AC voltage exists, go to next step. 4. Check for AC voltage that varies with engine RPM between Light Green/Black and White wires. If voltage does not exist, replace vehicle speed buffer. If voltage exists, go to next step. 5. Turn ignition off. Reconnect VSS. Start engine. Put transmission into gear. Backprobe VSS connector. Check for AC voltage that varies with engine RPM between Yellow and Black/White wires. If voltage changes with RPM, replace VSS buffer.
Friday, September 10th, 2010 AT 4:23 PM