B2371

B2371-HORN CONTROL CIRCUIT OVERCURRENT





For a complete wiring diagram, refer to the Wiring Information.

- When Monitored:
With the ignition on.

Battery voltage greater than 10.4 volts.

- Set Condition:
An overcurrent condition in the (X21)/(X22) Horn Control Output circuit.





1. CHECK FOR ACTIVE DTC B2371-HORN CONTROL CIRCUIT OVERCURRENT
1. Turn the ignition on.
2. With the scan tool, record and erase DTCs.
3. Operate the Horn Switch several times.
4. With the scan tool, read DTCs.

Does the scan tool display active DTC B2371-HORN CONTROL CIRCUIT OVERCURRENT?

Yes

- Go To 2

No

- Test complete, the condition or conditions that originally set this DTC are not present at this time. Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals, and correct pin tension.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

2. VISUAL AND PHYSICAL CONNECTOR AND TERMINAL INSPECTION
1. Turn the ignition off.
2. Inspect the following connector terminal condition. Check for signs of corrosion build up or damage that would compromise the terminal to controller pin connector.

NOTE: Make sure that all in-line connectors are inspected for corrosion and/or damage.

3. Disconnect the Horn connectors.
4. Disconnect the TIPM C11 harness connector.
5. Visually inspect the wiring harness. Look for any chafed, pierced, pinched or partially broken wires hidden in the wire insulation.

Were any of the above conditions found?

Yes

- Repair or replace as necessary.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Go To 3

3. (X21)/(X22) HORN CONTROL OUTPUT CIRCUIT HIGH RESISTANCE




1. With a jumper wire, connect one end to the (X21) Horn Control Output circuit at the Horn connector and the other to a clean chassis ground.
2. Using a 12-volt test light to battery voltage, check the (X21) Control Output circuit in the TIPM C11 harness connector.

NOTE: Cavity 8 at the C11 TIPM harness connector is for export vehicles only.

NOTE: If this is an export vehicle, follow the previous steps for the (X22) Horn Control Circuit also.

NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.

Does the test light illuminate brightly?

Yes

- Go To 4

No

- Repair the excessive resistance in the Horn Control Output circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

4. CHECKING HORN OPERATION
1. Turn the ignition off.
2. Disconnect the horn(s) connector(s) if not disconnected.
3. Momentarily jumper 12-volts to the horn(s).

Did the horn(s) operate properly?

Yes

- Go To 6

No

- Go To 5

5. CASE GROUND CIRCUIT OPEN
1. Using a 12-volt test light connected to 12-volts, check the case ground at the horn(s) case.

Does the test light illuminate brightly?

Yes

- Replace the Horn(s) as necessary.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Repair the open or excessive resistance at the horn(s) case ground.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

6. TOTALLY INTEGRATED POWER MODULE (TIPM)

NOTE: Before continuing, check the TIPM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary.

1. Using the schematics as a guide, inspect the wire harness and connectors.
2. Pay particular attention to all Power and Ground circuits.

Were any problems found?

Yes

- Repair as necessary.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

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