Fuel Pump Control Open Circuit (Ford)
What does P1236 mean?
The P1236 code means the vehicle's onboard diagnostic system has detected: Fuel Pump Control Open Circuit (Ford). This is a critical severity code.
Common Symptoms
- Check Engine Light on
- Engine stalls intermittently
- Hard starting or no start
- Loss of fuel pressure
- Engine dies at idle
Probable Causes (Ranked by Likelihood)
- Open circuit in fuel pump driver module wiring Very High
- Failed fuel pump driver module High
- Corroded fuel pump relay connector Moderate
- Damaged wiring harness near fuel tank Moderate
- PCM fuel pump control driver failure Low
Step-by-Step Diagnostic Procedure
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Check FPDM connector for open or corroded pins
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Measure resistance in wiring between PCM and FPDM
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Test fuel pump relay operation and connector integrity
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Inspect wiring harness routing near fuel tank for damage
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Verify PCM fuel pump control output with a scan tool
Frequently Asked Questions
What does P1236 mean on a Ford?
P1236 indicates an open circuit in the fuel pump control system. The PCM cannot communicate with the fuel pump driver module, which can cause the fuel pump to stop working or operate erratically.
Can I drive with P1236?
No. An open circuit in the fuel pump control can cause the engine to stall without warning. Have the vehicle towed to a repair shop.
Is P1236 expensive to fix?
It depends on the cause. A corroded connector may cost under $200, while a failed FPDM with labor can run $400-$750. Always diagnose the root cause before replacing parts.