What Does B1822 Mean?
This code indicates that the Body Control Module (BCM) has detected an electrical fault in the rear wiper park position sensor circuit. The park sense switch is responsible for signaling when the rear wiper blade has returned to its rest position after being turned off. The BCM detected either an open circuit, short circuit, or improper voltage signal from this input circuit, preventing proper rear wiper park function verification.
Common Causes
45%
Faulty rear wiper motor park switch or corroded contacts within the wiper motor assembly
30%
Damaged or chafed wiring harness between BCM and rear wiper motor, often due to liftgate flexing
15%
Corroded or loose electrical connector at rear wiper motor or BCM
10%
Failed Body Control Module (BCM) with internal circuit board damage
Diagnostic Steps
1
Step 1: Visually inspect the rear wiper motor connector and wiring harness in the liftgate area for visible damage, corrosion, water intrusion, or chafing from repeated liftgate opening/closing. Check connector pin tension and look for green corrosion.
2
Step 2: Using a digital multimeter, backprobe the park sense circuit at the rear wiper motor connector while cycling the wiper on and off. Verify voltage transitions between 0V and 12V (or 5V reference depending on manufacturer) when wiper moves to park position. Consult wiring diagram for specific pin identification.
3
Step 3: Disconnect rear wiper motor connector and check for continuity between the park sense signal wire and ground, then between signal wire and power. Infinite resistance in both tests indicates proper circuit isolation. Low resistance indicates a short circuit in the harness.
4
Step 4: If wiring tests pass, remove rear wiper motor assembly and bench test the internal park switch using an ohmmeter. Manually rotate the motor gear to park position and verify switch closure/opening. Replace motor if switch is faulty.
5
Step 5: Clear codes, reinstall components, and cycle rear wiper through multiple on/off cycles to verify proper park function and confirm code does not return. Monitor BCM data stream for proper park sense input signal.
Estimated Repair Cost
$150 - $450
Parts + labor, varies by vehicle and location
This code indicates that the Body Control Module (BCM) has detected an electrical fault in the rear wiper park position sensor circuit. The park sense switch is responsible for signaling when the rear wiper blade has returned to its rest position after being turned off. The BCM detected either an op...
The most common cause of B1822 (Wiper Rear Park Sense Input Circuit Failure) is: Faulty rear wiper motor park switch or corroded contacts within the wiper motor assembly
Typical repair costs for B1822 range from $150 to $450, depending on the vehicle, location, and whether you do it yourself or go to a shop.
This code does not affect vehicle safety or drivability and the vehicle is safe to drive. The rear wiper may not automatically park in the correct position when turned off, which is a convenience issue rather than a safety concern, but should be repaired when convenient.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to B1822 to identify the root cause.
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Quick Info
Category
Body
System
Body Control / Wiper System
Difficulty
Type
Manufacturer
Recommended Tools
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