B2336

B2336-HORN CONTROL CIRCUIT LOW - FCM





For a complete wiring diagram Consult Diagrams/Electrical.

- When Monitored:
Continuously.

- Set Condition:
If the Front Control Module (FCM) senses either excessively low or no voltage on the (X4) Horn Relay Control circuit.





Diagnostic Test

1. TEST FOR INTERMITTENT CONDITION
Turn the ignition on.
With the scan tool, record and erase DTCs.
Operate the Horn Switch several times.
Cycle the ignition from on to off three times and leave on.
With the scan tool, read DTCs.
Does the scan tool display: B2336 HORN CONTROL CIRCUIT LOW?

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 BODY VERIFICATION TEST - VER 1. Body Verification Test.

2. CHECK THE HORN FUSE




Turn the ignition off.
Remove and inspect the Horn fuse.
Is the Horn Fuse open?

Yes

- Go To 3

No

- Reinstall the Horn Fuse. Then, Go To 7.

3. CHECK FOR A SHORTED HORN RELAY




Install a known good relay in place of the Horn Relay.
Replace the Horn fuse.
Turn the ignition on.
With the scan tool, record and erase DTCs.
Operate the Horn Switch several times.
Cycle the ignition from on to off three times and leave on.
With the scan tool, read DTCs.
Does the scan tool display: B2336 HORN CONTROL CIRCUIT LOW?

Yes

- Go To 4

No

- Replace the original Horn Relay.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.

4. CHECK THE (A43) FUSED B(+) CIRCUIT FOR A SHORT TO GROUND




Turn the ignition off.
Remove the Horn Relay.
Remove the Horn Fuse.
Measure the resistance of the (A43) Fused B(+) circuit between ground and Cavity 86 of the Horn Relay connector in the Integrated Power Module (IPM).
Measure the resistance of the (A43) Fused B(+) circuit between ground and Cavity 30 of the Horn Relay connector in the Integrated Power Module (IPM).
Is the resistance below 10k ohms?

Yes

- Replace the Integrated Power Module (IPM).
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.

No

- Go To 5

5. CHECK THE (X4) HORN RELAY CONTROL CIRCUIT FOR A SHORT TO GROUND




Remove the Front Control Module (FCM).
Measure the resistance of the (X4) Horn Relay Control circuit between ground and Cavity 85 of the Horn Relay connector in the Integrated Power Module (IPM).
Is the resistance below 10k ohms?

Yes

- Replace the Integrated Power Module (IPM).
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.

No

- Replace the Front Control Module (FCM). Then, Go To 6.

6. CHECK FOR A SHORTED INTEGRATED POWER MODULE (IPM)




Install the original Horn Relay.
Replace the Horn fuse.
Turn the ignition on.
With the scan tool, record and erase DTCs.
Operate the Horn Switch several times.
Cycle the ignition from on to off three times and leave on.
With the scan tool, read DTCs.
Does the scan tool display: B2336 HORN CONTROL CIRCUIT LOW?

Yes

- Replace the Integrated Power Module (IPM).
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.

No

- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.

7. CHECK FOR POWER TO THE HORN FUSE




Turn the ignition on.
Using a 12-volt test light connected to ground, check for power to the Horn Fuse.
Does the test light illuminate brightly?

Yes

- Go To 8

No

- Repair the (A1) / (A913) circuit for an open.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.

8. CHECK FOR AN OPEN HORN RELAY




Turn the ignition off.
Install a known good relay in place of the Horn Relay.
Turn the ignition on.
With the scan tool, record and erase DTCs.
Operate the Horn Switch several times.
Cycle the ignition from on to off three times and leave on.
With the scan tool, read DTCs.
Does the scan tool display: B2336 HORN CONTROL CIRCUIT LOW?

Yes

- Go To 9

No

- Replace the original Horn Relay.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.

9. CHECK THE (A43) FUSED B(+) CIRCUIT FOR AN OPEN




Turn the ignition off.
Remove the Horn Relay.
Remove the Horn Fuse.
Measure the resistance of the (A43) Fused B(+) circuit between the Horn Fuse (output cavity) and Cavity 86 of the Horn Relay connector in the Integrated Power Module (IPM).
Measure the resistance of the (A43) Fused B(+) circuit between the Horn Fuse (output cavity) and Cavity 30 of the Horn Relay connector in the Integrated Power Module (IPM).
Is the resistance below 5.0 ohms?

Yes

- Go To 10

No

- Replace the Integrated Power Module (IPM).
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.

10. CHECK THE (X4) HORN RELAY CONTROL CIRCUIT FOR AN OPEN




Remove the Front Control Module (FCM).
Measure the resistance of the (X4) Horn Relay Control circuit between Cavity 85 of the Horn Relay connector in the Integrated Power Module (IPM) and Cavity 47 of the FCM 49-Way connector.
Is the resistance below 5.0 ohms?

Yes

- Replace the Front Control Module (FCM).
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.

No

- Replace the Integrated Power Module (IPM).
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.