P1683

Tests 1 - 2:

Tests 3 - 6:

Tests 7 - 11:

Tests 12 - 15:

SYMPTOM
P1683 - SPEED CONTROL POWER RELAY OR S/C 12V DRIVER CIRCUIT

POSSIBLE CAUSES
- Ground circuit open
- S/C brake switch output circuit shorted to ground
- S/C brake switch output circuit open
- S/C power supply circuit open
- S/C servo
- Brake switch
- Brake switch out of adjustment
- S/C vacuum solenoid control circuit open
- S/C vacuum solenoid control circuit shorted to ground
- S/C vent solenoid control circuit open
- S/C vent solenoid control circuit shorted to ground
- Powertrain Control Module (speed control)