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 Ω between the test points: Ground circuit terminal C & Ground
- If 10 Ω or greater
1. Test for less than 2 Ω between the test points: Ground circuit terminal C @ Component harness & The other end of the circuit
  - If 2 Ω or greater - Repair the open/high resistance in the circuit.
  - If less than 2 Ω - Repair the open/high resistance in the ground connection.
- Go to next step: If less than 10 Ω
Ignition - On/Vehicle - In Service Mode
Verify DTC P257E is not set.
- If the DTC is set
1. Test for infinite resistance between the test points: Signal circuit terminal A @ Component harness & The other end of the circuit
  - If less than infinite resistance - Repair the short to ground on the circuit.
  - If infinite resistance - Replace the component: K20 Engine Control Module
  - Go to next step: If the DTC is not set
Connect a 5 A fused jumper wire between the test points: Signal circuit terminal A & Ground
Verify DTC P257F is not set.
- If the DTC is set
1. Ignition/Vehicle - Off
2. Disconnect the electrical connector: K20 Engine Control Module
3. Test for less than 1 V between the test points: Signal circuit terminal B @ Component harness & Ground
  - If 1 V or greater - Repair the short to voltage on the circuit.
  - Go to next step: If less than 1 V
4. Test for less than 2 Ω between the test points: Signal circuit terminal B & The other end of the circuit
- If 2 Ω or greater - Repair the open/high resistance in the circuit.
- If less than 2 Ω - Replace the component: K20 Engine Control Module
- Go to next step: If the DTC is not set
Test or replace the component: B55 Engine Hood Switch