DD15 SPN 84/FMI 3 Troubleshooting

SPN 84/FMI 3

This diagnostic condition is typically VSS open circuit.‪

Check as follows:‪

1. Disconnect the Vehicle Speed Sensor (VSS).
2. Measure the resistance between pin 13 of the CPC connector #3 (21–pin) and pin 1 of the VSS.
   1. If the resistance is greater than 3 Ω, repair the open between pin 13 of the CPC connector #3 (21–pin) and pin 1 of the VSS. Refer to “23.2.1.1 Verify Repairs” .
   2. If the resistance is less than 3 Ω, go to the next step.
3. Measure the resistance between pin 14 of the CPC connector #3 (21–pin) and pin 2 of the VSS sensor.
   1. If the resistance is greater than 3 Ω, repair the open wire between pin 14 of the CPC #3 connector (21–pin) and pin 2 of the VSS. Refer to “23.2.1.1 Verify Repairs” .
   2. If the resistance is less than 3 Ω, go to the next step.
4. Measure the resistance between pin 13 of the CPC connector #3 (21–pin) and pin 1 of the VSS sensor.
   1. If the resistance greater than 3 Ω, replace the VSS. Refer to “23.2.1.1 Verify Repairs” .
   2. If the resistance is less than 3 Ω, repair the short in the harness between pins 13 and 14 of the CPC connector #3 (21–pin). Refer to “23.2.1.1 Verify Repairs” .