B1473
Wiper Low 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

The wiper motor isn't responding properly at low speed, similar to a fan that won't spin slowly even though the power switch is on. The ECU detected a circuit fault preventing the motor from operating at reduced speeds.

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Symptoms You May Notice
3 known symptoms for this code
Wipers do not move at low speed setting
Wipers may work only at high speed or not at all
Wiper control stalk functions but produces no motor response
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Embedded Systems Insight
What the ECU/ECM is actually computing

The ECU monitors motor current draw and speed feedback from the wiper motor circuit at low-speed commands. It compares actual motor behavior against expected resistance and RPM thresholds. A fault is triggered when current flow is absent, excessive, or motor speed fails to match the command signal.

Voltage & Parameter Thresholds

Parameter Normal Range Fault Condition
Low-speed motor current draw 2-5 amps at low speed 0 amps or >8 amps detected
Motor response time Motor engages within 500ms No motor engagement or >2 second delay
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Diagnostic & DIY Fix Guide
Check these in order — from cheapest to most complex
1
Wiper motor relay
Locate the relay in the fuse box using the diagram, remove it, and swap with an identical relay from another circuit to test if operation restores.
2
Wiper motor connector
Disconnect the motor harness under the hood, inspect pins for corrosion or damage, clean with contact cleaner, and reconnect firmly.
3
Wiper motor assembly
Remove the motor mounting bolts and replace the entire motor unit if relay and connections test good.