B1815
Low Severity (Level 2)Wiper Rear Motor Down Relay Coil Circuit Open
B1815 usually means wiper Rear Motor Down Relay Coil Circuit Open.
Can you still drive with B1815?
⚠️Short-distance driving is usually OK, but have this diagnosed within a week to prevent further damage.
Typical repair cost: $60 – $400
Severity Level 2 — Low
This code indicates a minor issue that is unlikely to cause immediate driveability problems. You can typically continue driving but should have the vehicle inspected at your earliest convenience.
Common Symptoms
- Windshield wipers not working, stuck mid-cycle, or only working on one speed
- Wipers won't park (return to rest position) when turned off
- Windshield wipers not working — no response when activated
- Infinite resistance in the wiper/washer circuit — broken wire or disconnected connector
Possible Causes
- Broken wire or connector pin in the wiper/washer system harness — common at flex points like door jambs or where wiring moves
- Disconnected or loose electrical connector — may have been bumped during other repairs
- Failed wiper motor — internal open circuit from age, heat cycling, or vibration
- Corrosion completely severing a wire or connector terminal — green crust on copper wiring
- Wiring harness damage from rodent chewing — look for nesting material near the engine or under dash
Common Fixes
- Scan vehicle with a professional-grade OBD2 scanner to read all stored codes and freeze frame data — note the conditions when the code set ($7-91 at shop, free at auto parts store for basic scan)
- Visually inspect the wiper/washer system wiring harness and connectors — look for chafed wires, melted insulation, green corrosion, loose pins, or rodent damage (often free to check yourself, $117 diagnostic fee at shop)
- Trace the wiper/washer system wiring from connector to connector with a multimeter set to continuity/resistance mode — find and repair the break in the circuit ($112-418 labor for diagnosis and repair)
- Check and reseat all connectors in the wiper/washer system circuit — disconnect, inspect pins, clean with electrical contact cleaner, apply dielectric grease, and reconnect firmly ($11 DIY or $81 shop minimum)
- If wiper motor has failed internally (open circuit inside), replace it — don't try to repair sealed components ($50-400)
Estimated Repair Cost
These are estimated costs based on generic repair data. Actual costs may vary depending on your vehicle, location, and labor rates.
Frequently Asked Questions
What does B1815 mean?
B1815 stands for "Wiper Rear Motor Down Relay Coil Circuit Open". B1815 usually means wiper Rear Motor Down Relay Coil Circuit Open.
Can you drive with B1815?
Short-distance driving is usually OK, but have this diagnosed within a week to prevent further damage.
How much does it cost to fix B1815?
Repair costs for B1815 typically range from $60 to $400, depending on your vehicle make, model, and local labor rates. Common fixes include: Scan vehicle with a professional-grade OBD2 scanner to read all stored codes and freeze frame data — note the conditions when the code set ($7-91 at shop, free at auto parts store for basic scan); Visually inspect the wiper/washer system wiring harness and connectors — look for chafed wires, melted insulation, green corrosion, loose pins, or rodent damage (often free to check yourself, $117 diagnostic fee at shop); Trace the wiper/washer system wiring from connector to connector with a multimeter set to continuity/resistance mode — find and repair the break in the circuit ($112-418 labor for diagnosis and repair).
Will B1815 clear itself?
Explore Repair Costs
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