Circuit/System Testing

NOTE:

Use the schematics to verify the items listed below:
- The control module's B+, and ground circuits.
- The control module terminal numbers.
Some control module ground circuits may require up to 20 min after the ignition is turned Off before achieving a resistance reading of less than 5 Ω. In most cases the readings will drop below 20 Ω within 1 min indicating the control modules are going to sleep.

Ignition Off, disconnect the connector (s) at the appropriate control module.
Verify a test lamp illuminates between each ground circuit terminal and B+
- If the test lamp does not illuminate
  Repair the open/high resistance on circuit or the ground connection.
- Go to next step: If the test lamp illuminates
Ignition ON.
Verify a test lamp illuminates between each B+ circuit terminal and ground.
- If the test lamp does not illuminate and the circuit fuse is good
1. Test the B+ circuit for an open/high resistance.
  - If an open/high resistance is found, repair the fault on the circuit.
  - Go to next step: If an open or high resistance is not found
2. Verify the fuse is not open and there is voltage at the fuse.
- If the test lamp does not illuminate and the circuit fuse is open
1. Test the B+ circuit a short to ground
  - If a short to ground is found, repair the fault on the circuit.
  - Go to next step: If a short to ground is not found
2. Replace the control module.
- Go to next step: If the test lamp illuminates
Verify voltage at each B+ circuit terminal is within 1 V of the C1 Battery voltage.
- If not the specified value
  Repair the high resistance on B+ circuit.
- Go to next step: If the specified value
Verify a test lamp illuminates between each ignition circuit terminal and ground.
- If the test lamp does not illuminate and the circuit fuse is good
1. Test the ignition circuit for an open/high resistance.
  - If an open/high resistance is found, repair the fault on the circuit.
  - Go to next step: If an open or high resistance is not found
2. Verify the fuse is not open and there is voltage at the fuse.
- If the test lamp does not illuminate and the circuit fuse is open
1. Test the ignition circuit a short to ground
  - If a short to ground is found, repair the fault on the circuit.
  - Go to next step: If a short to ground is not found
2. Replace the control module.
- Go to next step: If the test lamp illuminates
Verify voltage at each ignition circuit terminal is within 1 V of the C1 Battery voltage.
- If not the specified value
  Repair the high resistance on ignition circuit.
- Go to next step: If the specified value
Replace the control module.