B2115: Rear Washer Input Short to Ground
The B2115 code indicates that the Body Control Module (BCM) or Generic Electronic Module (GEM) has detected a short to ground in the rear washer switch input circuit. This happens when the voltage on the signal wire from the rear washer switch drops continuously near 0 volts, preventing the module from sensing the driver's request to activate the rear washer.
1. Commonly Affected Makes
2. Most Common Causes
- Rear washer switch (on steering column stalk or panel) internally shorted to ground
- Wiring harness for the rear washer signal circuit chafed or pinched against chassis/body
- Corrosion, moisture, or bent pins in the BCM/GEM or switch connector causing a ground contact
- Internal failure of the input driver in the BCM/GEM
3. Symptoms You Will Notice
- Rear windshield washer does not operate when switch is activated
- Rear wiper may still work but washer fluid does not spray
4. Step-by-Step Diagnosis
Check for technical service bulletins (TSBs) related to rear washer circuit
Inspect the rear washer switch and its connector for damage, corrosion, or bent pins
Test the signal wire from the switch to the BCM/GEM for continuity to ground (should not be shorted)
If wiring and switch are okay, suspect a faulty BCM/GEM and perform module self-test
5. Frequently Asked Questions
Is it safe to drive?▼
Yes, it is generally safe to drive. The rear washer will not function, but the vehicle remains drivable. However, reduced visibility in rain or snow may occur if the rear window gets dirty.
How much does it cost to fix?▼
Repair costs typically range from $100 to $400, depending on the cause. A switch replacement is on the lower end, while BCM/GEM replacement and programming can be higher.