C1241 Code: ABS Pressure Differential Switch Short to Ground
🟠 Moderate severity · drivable
The car is usually still drivable, but the ABS light may be on and anti-lock braking may not work.
What C1241 means
The ABS hydraulic pressure differential switch checks the brake pressure in the two brake circuits. This code means the switch circuit is shorted to ground, so the ABS computer sees no signal or a bad signal. The anti-lock brakes may be turned off, but normal braking usually still works.
Symptoms
- ABS warning light on the dash
- Brake warning light on
- Anti-lock braking may not engage
- ABS system inactive during hard stops
Common causes
- most common: Damaged wiring in the ABS harness shorted to ground
- common: Faulty pressure differential switch
- less common: Corroded connector or terminals
- rare: Failed ABS control module
How to fix it
| Fix | DIY? | Typical cost |
|---|---|---|
| Inspect the ABS wiring and fix the short to ground | Yes | $20–100 |
| Replace the pressure differential switch | Yes | $50–150 |
| Clean or replace the ABS connector and terminals | Yes | $10–40 |
| Replace the ABS control module | Mechanic | $300–800 |
Frequently asked questions
Can I drive with C1241?
Yes, the normal brakes usually still work, but the ABS is disabled. Get the wiring checked soon so the fault does not spread to other circuits.
What is the difference between C1240 and C1241?
C1240 is a short to battery power and C1241 is a short to ground. Both point to the same pressure switch circuit, just different faults.
How do I find the short in the ABS wiring?
Use a multimeter to check the switch circuit for unwanted continuity to ground with the power off. Inspect the harness where it rubs against metal or sharp edges.
Related codes
Updated 2026-08. This page is informational and not a substitute for professional diagnosis.