What Does B1241 Mean?
This code indicates that the Body Control Module (BCM) has detected an unintended voltage source on the rear wiper washer pump relay control circuit. The BCM detected battery voltage present on the control side of the relay when it should be at ground or no voltage, suggesting a short to power condition. This prevents the BCM from properly controlling the rear washer pump relay operation.
Common Causes
40%
Damaged or chafed wiring harness causing short to battery voltage in relay control circuit
30%
Failed rear wiper washer pump relay with internal short to power
20%
Corroded or damaged BCM connector pins creating cross-circuit short
10%
Faulty Body Control Module with internal circuit failure
Diagnostic Steps
1
Step 1: Perform visual inspection of rear wiper washer pump relay, wiring harness from BCM to relay, and all associated connectors for obvious damage, melting, chafing, or corrosion. Pay special attention to areas where harness passes through body panels or near sharp edges.
2
Step 2: Disconnect the rear washer pump relay and measure voltage at the relay control terminal from the BCM using a digital multimeter. With ignition on and washer switch off, reading should be 0-1V. If battery voltage (12V+) is present, trace the control wire back toward BCM for short to power.
3
Step 3: With relay still disconnected, check for continuity between the relay control wire and known power sources (fuse box, other circuits) using multimeter in ohms mode. Resistance below 10 ohms indicates a direct short requiring harness repair or replacement.
4
Step 4: If wiring tests normal, substitute a known good relay and clear codes. Cycle the rear washer function multiple times while monitoring live data for fault return. If code returns immediately, suspect BCM internal failure.
5
Step 5: Inspect BCM connector for pushed-out pins, corrosion, or moisture intrusion that could cause cross-circuit contamination. Clean and repair connector as needed, apply dielectric grease, and retest system operation after clearing codes.
Estimated Repair Cost
$75 - $450
Parts + labor, varies by vehicle and location
This code indicates that the Body Control Module (BCM) has detected an unintended voltage source on the rear wiper washer pump relay control circuit. The BCM detected battery voltage present on the control side of the relay when it should be at ground or no voltage, suggesting a short to power condi...
The most common cause of B1241 (Wiper Washer Rear Pump Relay Circuit Short to Battery) is: Damaged or chafed wiring harness causing short to battery voltage in relay control circuit
Typical repair costs for B1241 range from $75 to $450, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Vehicle is safe to drive as this only affects rear window cleaning capability. Repair at convenience, though rear visibility may be compromised in poor weather conditions if washer system is inoperative.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to B1241 to identify the root cause.
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Quick Info
Category
Body
System
Body Electrical System
Difficulty
Type
Manufacturer
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