Circuit/System Testing

NOTE:

It may take up to 2 min for all vehicle systems to power down before an accurate ground or low reference circuit continuity test can be performed.

Ignition/Vehicle & All vehicle systems - Off
Disconnect the electrical connector: B55 Hood Ajar Switch
Test for less than 10 ohms between the test points: Ground circuit terminal 3 & Ground
- If 10 ohms or greater
1. Ground Connection - Disconnect
2. Test for less than 2 ohms between the test points: Ground circuit terminal 3 & Ground Connection
  - If 2 ohms or greater - Repair the open/high resistance in the circuit.
  - If less than 2 ohms - Repair the open/high resistance in the ground connection.
- Go to next step: If less than 10 ohms
Ignition - On/Vehicle - In Service Mode
Test for greater than 10.5 V between the test points: Signal circuit terminal 1 & Ground
- If less than 10.5 V
1. Ignition/Vehicle - Off
2. Disconnect the electrical connector: K20 Engine Control Module
3. Test for infinite resistance between the test points: Signal circuit terminal 1 @ Component harness & Ground
  - If less than infinite resistance - Repair the short to ground on the circuit.
  - Go to next step: If infinite resistance
4. Test for less than 2 ohms between the test points: Signal circuit terminal 1 @ Component harness & The other end of the circuit @ Control module harness
  - If 2 ohms or greater - Repair the open/high resistance in the circuit.
  - If less than 2 ohms - Replace the component: K20 Engine Control Module
- Go to next step: If greater than 10.5 V
Ignition/Vehicle - Off
Disconnect the electrical connector: K20 Engine Control Module
Ignition - On/Vehicle - In Service Mode
Test for less than 1 V between the test points: Signal circuit terminal 1 @ Component harness & Ground
- If 1 V or greater - Repair the short to voltage on the circuit.
- If less than 1 V - Replace the component: B55 Hood Ajar Switch
Test or replace the component: K20 Engine Control Module