| STEP | OPERATIONS TO BE CARRIED OUT | TEST RESULTS | 
|---|
| 1 | COMPONENT CHECK | ALL OK | PROBLEMS ENCOUNTERED | ACTION | 
|---|
|  | Check the condition of the fuse in the engine compartment junction unit.  (Wiring Diagram    )  E3010  HORNS | Move on to Step | Fuse faulty | Replace the protective fuse (Wiring Diagram    )  E3010  HORNS | 
| 2 | ELECTRICAL SYSTEM CHECK | ALL OK | PROBLEMS ENCOUNTERED | ACTION | 
|---|
|  | Check for the output positive from the engine compartment junction unit to the steering column switch unit (Wiring Diagram    )  E3010  HORNS | Move on to Step | No positive | Move on to Step | 
| 3 | COMPONENT CHECK | ALL OK | PROBLEMS ENCOUNTERED | ACTION | 
|---|
|  | Check the internal continuity of the engine compartment junction unit between: Check the condition of the relay feed (Wiring Diagram    )  E3010  HORNSprotective fuse and horn relay feedrelay feed and output to steering column switch unitrelay feed and output to horns.
 | Move on to Step | 1. Connections inside junction unit broken | 1. Replace the engine compartment junction unit    See in Op.   5505A13  Additional junction unit in engine compartment - R.R. | 
| 2. Relay feed faulty | 2. Replace the relay feed (Wiring Diagram    )  E3010  HORNS | 
| 4 | ELECTRICAL SYSTEM CHECK | ALL OK | PROBLEMS ENCOUNTERED | ACTION | 
|---|
|  | Check the output earth for the horn from the engine compartment junction unit to the steering column switch unit by pressing the horn contact.  (Wiring Diagram    )  E3010  HORNS | Move on to Step | No earth | Move on to Step | 
| 5 | ELECTRICAL SYSTEM CHECK | ALL OK | PROBLEMS ENCOUNTERED | ACTION | 
|---|
|  | check the continuity between engine compartment junction unit and input on steering column switch unitsteering column switch unit and connection on steering wheel after the clock springconnection on steering wheel and output to earth from steering column switch unitoutput from steering column switch unit to centre dashboard earthhorn contacts on steering wheel (Wiring Diagram    )  E3010  HORNS 
 | Move on to Step | 1. No continuity between engine compartment junction unit. | 1. Restore the electrical connection (Wiring Diagram    )  E3010  HORNS | 
| 2. No continuity between steering wheel connection and steering column switch unit input/output | 2. Replace the steering column switch unit/clock spring assembly    See in Op.   5550A12  complete stalk unit - r+r for versions with air bag | 
| 3. No continuity between steering column switch unit and centre dashboard earth | 3. Restore the electrical connection (Wiring Diagram    )  E3010  HORNS | 
| 4. No continuity between horn contacts on steering wheel | 4. Replace the steering wheel    See in Op.   4110A11  STEERING WHEEL - R.R. for replacement or checks for versions with AIR BAG | 
| 6 | ELECTRICAL SYSTEM CHECK | ALL OK | PROBLEMS ENCOUNTERED | ACTION | 
|---|
|  | Check the continuity between: engine compartment junction unit and hornshorns and right front earth
 | Move on to Step | Electrical connection faulty | Restore the electrical connection (Wiring Diagram    )  E3010  HORNS | 
| 7 | COMPONENT CHECK | ALL OK | PROBLEMS ENCOUNTERED | ACTION | 
|---|
|  | check the condition of the horns | Move on to Step | Horns faulty | Replace the horns.     See in Op.   5550B30  Left or right HORN (one) - R.R. | 
| 8 | CHECK ON CORRECT OPERATION | ALL OK | PROBLEMS ENCOUNTERED | ACTION | 
|---|
|  | Check that the fault is no longer present |  |  |  |