Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Code A039: Front Enable Relay Open Or Contacts Shorted To Battery
The front enable relay is de-energized when front enable relay control is open. This blocks voltage application to the front solenoid and solenoid control. When front enable relay circuit No. 150 is open, battery voltage from ANTI-LOCK warning indicator will be routed to solenoids, even with front enable relay de-energized. To set Code A039, the following conditions must occur.
- Front enable relay control does not energize.
- Anti-lock brake controller senses battery voltage at terminals 1D1, 1C3, 1C6 and 1C9.
- If Code A040 is set, replace anti-lock brake controller.
- If Code A003 is set, inspect for open in circuit No. 150.
- Isolates short to battery in wire harness or anti-lock brake controller.
- Isolates a short to battery in circuit No. 962, or a defective front enable relay.
- If Code A039 is consistent, the anti-lock brake controller has internal malfunction.
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.