P1835: Transfer Case Relay Short to Battery
The P1835 code indicates that the Transfer Case Control Module (TCCM) has detected a short circuit to battery voltage (B+) in the counterclockwise relay coil circuit of the transfer case shift motor. This relay controls motor direction to engage or disengage low range (4Low) or 4WD. A short to battery keeps the relay permanently energized or damages the module's internal driver, preventing precise actuator control.
01. Most Common Causes
- Transfer case counterclockwise relay with internal coil short circuit
- Wiring harness chafed or pinched against chassis or power wire (short to B+)
- Relay or transfer case connector corroded, wet, or with bent pins causing a 12V bridge
- Transfer case control module (TCCM) with damaged output driver (internal short to battery)
- Transfer case shift motor internal failure feeding voltage back to relay circuit
02. Symptoms You Will Notice
- 4WD or low range inoperative or stuck engaged
- Service 4WD warning light illuminated
03. Step-by-Step Diagnosis
Scan for codes and verify P1835 is present
Inspect relay and connector for corrosion, damage, or bent pins
Check wiring for shorts to B+ using a multimeter
Test relay coil resistance and operation
If wiring and relay are good, suspect TCCM or shift motor failure
1. Frequently Asked Questions
Is it safe to drive?▼
No, driving with this code is not recommended as it can cause unintended engagement of 4WD or low range, leading to driveline damage or loss of control.
How much does it cost to fix?▼
Repair costs typically range from $200 to $800, depending on whether the issue is a simple relay replacement or requires a new TCCM or shift motor.