B1820

B1820-HOOD AJAR INPUT CIRCUIT HIGH







- When Monitored:
With the ignition on.

- Set Condition:
When the Totally Integrated Power Module (TIPM) senses 12 volts on the Hood Ajar Switch Sense circuit for over 10 seconds, this code will set.





1. TEST FOR INTERMITTENT CONDITION

NOTE: Open the hood and make sure the Hood Security Switch is connected before proceeding

1. With the scan tool, record and erase DTCs
2. Close the hood.
3. Cycle the ignition from on to off.
4. Turn the ignition on.
5. Open then close the hood.
6. With the scan tool, read DTCs.

Does the scan tool display this DTC as active?

Yes

- Go To 2

No

- The conditions that caused this code to set are not present at this time. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

2. INCORRECT HOOD SECURITY SWITCH INSTALLED
1. Inspect the retainer ring on the hood security switch.
2. A dark brown retainer ring identifies the underhood security switch used for certain export applications, while a white retainer ring identifies the remote starter system application.

Is the correct switch installed?

Yes

- Go To 3

No

- Replace the Hood Ajar Switch.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

3. HOOD SECURITY SWITCH OPEN
1. Disconnect and remove the Hood Ajar Switch.
2. Depress the switch plunger and measure the resistance between the two terminals of the switch.

Is the resistance approximately 1000 ohms?

Yes

- Go To 4

No

- Replace the Hood Ajar Switch.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

4. (G931) SENSOR GROUND CIRCUIT OPEN




1. Using a 12-volt test light connected to 12-volts, check the (G931) Sensor Ground circuit.

Does the test light illuminate?

Yes

- Go To 5

No

- Repair the (G931) Sensor Ground circuit for an open.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

5. (G70) HOOD AJAR SWITCH SENSE CIRCUIT SHORT TO VOLTAGE




1. Disconnect the TIPM C1 harness connector.
2. Turn the ignition on.
3. Measure the voltage between the (G70) Hood Ajar Switch Sense circuit and ground.

Is there any voltage present?

Yes

- Repair the (G70) Hood Ajar Switch Sense circuit for a short to voltage.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Go To 6

6. (G70) HOOD AJAR SWITCH SENSE CIRCUIT OPEN




1. Turn the ignition off.
2. Measure the resistance of the (G70) Hood Ajar Switch Sense circuit between the TIPM C1 harness connector and the Hood Ajar Switch harness connector.

Is the resistance below 2.0 ohms?

Yes

- Replace the Totally Integrated Power Module (TIPM).
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Repair the (G70) Hood Ajar Switch Sense circuit for an open.
- Perform the BODY VERIFICATION TEST. Body Verification Test.