Wiper Speed Control Circuit Fault
The B1466 code indicates that the Body Control Module (MICU/BCM) on Honda/Acura vehicles has detected that the wiper speed control circuit (high/low) is not changing state as commanded. The MICU monitors feedback from the wiper motor speed relay and expects a change between high and low speeds. This code sets when the expected feedback is not received, often due to a faulty relay, motor winding issues, or wiring problems.
1. Commonly Affected Makes
2. Most Common Causes
- Faulty or damaged wiper speed relay
- Open or shorted high-speed winding in the wiper motor
- Damaged wiring between the MICU and wiper motor or relay
- Corroded or loose connectors in the wiper harness
- Internal failure of the MICU (Multiplex Integrated Control Unit)
- Worn or damaged contacts in the steering column combination switch
- Blown wiper circuit fuse or abnormal resistance
3. Symptoms You Will Notice
- Wipers only work at one speed (high or low)
- Wipers do not change speed when selected
- Wipers may not work at all
4. Step-by-Step Diagnosis
Check for blown fuses in the wiper circuit and replace if necessary.
Inspect the wiper speed relay and test for proper operation.
Test the wiper motor windings for continuity and shorts.
Examine wiring and connectors between the MICU and wiper motor for damage or corrosion.
Verify the steering column switch contacts are clean and functioning.
If all else fails, test the MICU for internal faults or replace it.
5. Frequently Asked Questions
Is it safe to drive?▼
Yes, but with reduced visibility in rain. The wipers may only work at one speed or not at all, so it's best to fix it promptly.
How much does it cost to fix?▼
Typically $150 to $400, depending on the root cause. A relay or fuse is cheap, but a new MICU can be expensive.