For 1990-2009 cars

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
DEFINITION: The content theft deterrent system is unable to sound the horn when setting off the alarm.
1 | Test the horn by pressing the horn switch on the steering wheel. Does the horn sound? | -- | Go to Step 2 | Go to Step 7
2 | Perform the BCM Input/Output test:

1. Turn off the IP dimmer switch.
2. Turn the ignition switch to the LOCK position.
3. Remove the BCM PRGRM fuse.
4. Turn the ignition switch to the ACC position. The BCM sounds 4 chimes, indicating the BCM type installed on the vehicle.
5. Within 1 second, turn the ignition switch from the ACC position to the LOCK position and back to the ACC position.

The BCM sounds any stored DTCs.

6. Turn the I/P dimmer switch to the DOME position.

The BCM enters the Input/Output test.

7. Cycle the IP dimmer switch from the DOME position to the OFF position and back to the DOME position in order to move to the next test.

The BCM runs the Input/Output test in numerical order.

The BCM flashes the fasten belts indicator and sounds the chime a number equivalent to the Input/Output test number:

• | Test 1 de-energizes CKT 1393 (protected courtesy light output).

• | Test 2 energizes CKT 1393.

• | Test 3 grounds CKT 690 (courtesy lights control).

• | Test 4 turns on the exterior lights.

• | Test 5 sounds the horn relay for 25 ms.

• | Test 6 turns on the security indicator lamp.

• | Test 7 turns off the theft security indicator lamp.

Does the horn sound when the BCM performs test 5?

--

Go to Step 4

Go to Step 3

3 | Did you perform the Body Control Module Diagnostic System Check? | -- | Go to Step 5 | Go to Diagnostic System Check - Body Control System in Body Control Systems
4 |

1. Turn the ignition switch to the LOCK position.
2. Reinstall the BCM PRGRM fuse.
3. Perform the Content Theft Deterrent (CTD) System Check .

Does the content theft deterrent system work as described in the Content Theft Deterrent System Check?

Go to Step 10

Go to Step 8

5 |

1. Disconnect the BCM connector C2.
2. Use a 10A fused jumper in order to connect momentarily between the BCM harness connector C2 terminal D10 and ground.

Upon connecting the fused jumper, does the horn sound?

--

Go to Step 6

Go to Step 9

6 |

1. Reconnect the BCM connector C2.
2. Perform the Content Theft Deterrent (CTD) System Check .

Does the content theft deterrent system work as described in the Content Theft Deterrent System Check?

--

Go to Step 10

Go to Step 8

7 | The content theft deterrent system is unable to sound the horn during an alarm event due to a malfunction with the vehicle horns. Refer to Horns System Check in Horns. Is the action complete? | -- | Go to Step 11 | --
8 |

1. Inspect the BCM connector C2 terminal D10 for a poor terminal contact.
2. If there is not poor terminal contact, replace the BCM. Refer to Body Control Module Replacement in Body Control System.

Is the repair complete?

--

Go to Step 11

--

9 | Repair the following conditions in CKT 28 between the BCM and the horn relay:

• | A poor connection

• | An open

Is the repair complete?

--

Go to Step 11

--

10 | A malfunction is not present at this time. Refer to Content Theft Deterrent (CTD) Circuit Description . Is the repair complete? | -- | Go to Step 11 | --
11 |

1. Turn the ignition switch to the LOCK position.
2. Reinstall the connectors/components removed.
3. Turn the ignition switch to the RUN position for 6 seconds.
4. Turn the ignition switch to the LOCK position.
5. Remove the BCM PRGRM fuse.
6. Turn the ignition switch to the ACC position. (The BCM flashes the fasten belts indicator and sounds the chime four times identifying the BCM type installed on the vehicle.)
7. Within 1 second, turn the ignition switch from the ACC position, to the LOCK position, then back to the ACC position. (The BCM sounds any DTCs stored.)

Are there any BCM DTCs present?

--

Go to Diagnostic System Check - Body Control System in Body Control System

Go to Content Theft Deterrent (CTD) System Check