DESCRIPTION & OPERATION
| WARNING | Vehicles are equipped with air bag supplemental restraint system. Before attempting any repairs involving steering column, instrument panel or related components, see SERVICE PRECAUTIONS and DISABLING & ACTIVATING AIR BAG SYSTEM in AIR BAG RESTRAINT SYSTEMS article. |
System Operation
The horn system consists of the following components
- The horn fuse.
- The horn relay.
- The inflatable restraint steering wheel coil.
- The horn switch (The horn switch is part of the inflatable restraint steering wheel module.)
- The horn assembly
- The dash integration module (DIM.)
The vehicle horn system is activated when the horn switch is depressed.
Circuit Operation
Battery positive voltage is applied at all times to the horn relay coil and the horn relay switch. Pressing the horn switch applies ground to the horn relay control circuit. The DIM may also apply ground to the horn relay control circuit as described above. When the horn relay control circuit is grounded, the horn relay is energized and battery positive voltage is applied to the horns through the horn control circuit. The horns sound as long as ground is applied to the horn relay control circuit.
Description
With cruise control, you can maintain a speed of about 25 MPH (40 km/h) or more without keeping your foot on the accelerator. This is helpful on long trips. Cruise control does not work at speeds below about 25 MPH (40 km/h). When you apply your brakes, the cruise control shuts off. If your vehicle is in cruise control when the traction control system begins to limit wheel spin, the cruise control will automatically disengage.
Test Description
The number(s) below refer to the step number(s) on the DIAGNOSTIC SYSTEM CHECK table.
- 2 Lack of communication may be due to a partial malfunction of the class 2 serial data circuit or due to a total malfunction of the class 2 serial data circuit. The specified procedure will determine the particular condition.
- 3 The symptoms list in «SYMPTOMS»(ref-129065-S35643245952002090400000) will determine the correct diagnostic procedure to use.
- 4 The presence of DTCs which begin with "U" indicate some other module is not communicating. The specified procedure will compile all the available information before tests are performed.
- 6 At this point you have determined all DTCs applicable to the horn system. Refer to «SYMPTOMS»(ref-129065-S35643245952002090400000) for further horn system diagnosis. Any other codes displayed from the listed modules do not apply to horns and should be diagnosed in the applicable section.
| Step | Action | Yes | No |
|---|---|---|---|
| 1 | Install A Scan Tool. Does The Scan Tool Power Up? | Go To Step 2 | See Scan Tool Does Not Communicate With Class 2 Device In BODY CONTROL MODULES - AURORA |
| 2 | Turn On The Ignition, With The Engine Off. Attempt To Establish Communication With The Dash Integration Module (DIM). Does The Scan Tool Communicate With The DIM? | Go To Step 3 | See Scan Tool Does Not Communicate With Class 2 Device In BODY CONTROL MODULES - AURORA |
| 3 | Select The DIM Display DTCs Function On The Scan Tool. Does The Scan Tool Display Any DTCs? | Go To Step 4 | See SYMPTOMS |
| 4 | Does The Scan Tool Display Any DTCs Which Begin With A "U"? | See Scan Tool Does Not Communicate With Class 2 Device In BODY CONTROL MODULES - AURORA | Go To Step 5 |
| 5 | Does The Scan Tool Display DTC B1000, B1004, B1007, B1009 Or B1010? | Go To Diagnostic Trouble Code (DTC) List In BODY CONTROL MODULES - AURORA | Go To Step 6 |
| 6 | Does The Scan Tool Display DTC B1327? | Go To Diagnostic Trouble Code (DTC) List In GENERATORS & REGULATORS - AURORA | See SYMPTOMS |
DIAGNOSTIC SYSTEM CHECK
| Scan Tool Output Control | Additional Menu Selection(s) | Description |
|---|---|---|
| Horn | Output Control | The Dash Integration Module (DIM) Activates The Horn Momentarily When You Select On |
SCAN TOOL OUTPUT CONTROLS