B1476
Wiper High Speed Circuit Motor Failure
Body Chassis/Safety Wiper System 🟢 Low — Fix at next service
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What This Actually Means
In plain language — no jargon

Your windshield wiper motor isn't responding when you set it to high speed, similar to a light switch that won't turn on even though the bulb works fine. The car's computer detected that the high-speed wiper circuit is failing to function properly.

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Symptoms You May Notice
3 known symptoms for this code
Wipers don't move or move slowly on high speed setting
Wipers work normally on low speed but not high speed
Intermittent wiper operation or complete failure at high speed
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Embedded Systems Insight
What the ECU/ECM is actually computing

The ECU monitors motor current draw and speed feedback when high-speed wipers are commanded. It detects open circuits, shorts, or mechanical binding by comparing actual motor response to expected electrical signatures. If current exceeds safe limits or motor fails to reach expected RPM, the fault is triggered.

Voltage & Parameter Thresholds

Parameter Normal Range Fault Condition
High-speed motor current draw 1.5–3.5 amps >4.5 amps or <0.5 amps
Motor speed response time Reaches speed within 500ms No response or delayed >2 seconds
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Diagnostic & DIY Fix Guide
Check these in order — from cheapest to most complex
1
Wiper motor electrical connector
Disconnect and reconnect the wiper motor harness, cleaning corrosion from contacts with a wire brush.
2
Wiper motor relay or module
Swap the wiper relay with an identical relay from another circuit to test if the relay is faulty.
3
Wiper motor assembly
Replace the wiper motor if electrical testing confirms it draws excessive current or has no continuity in high-speed circuits.