Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This means that the car's computer has detected a problem with the electrical circuit that controls the fuel pump. It's like when a light switch is supposed to be off, but it's stuck in the on position.
The P1236 code indicates that the voltage in the fuel pump relay circuit is higher than expected, which can affect the fuel pump's operation.
The fuel pump relay is responsible for supplying power to the fuel pump. When the PCM (Powertrain Control Module) detects a voltage level that is too high in the primary circuit of the fuel pump relay, it triggers the P1236 code. This could be due to an issue with the relay itself, wiring problems, or a fault in the PCM.
• Engine may not start
• Engine stalls
• Poor fuel economy
• Faulty fuel pump relay
• Wiring issues such as short circuits or open circuits
• Faulty Powertrain Control Module (PCM)
PCM: Powertrain Control Module, the computer that controls engine and transmission functions.
Relay: An electrical switch that opens and closes under the control of another electrical circuit.
• Check the fuel pump relay for proper operation.
• Inspect the wiring and connectors for damage or corrosion.
• Test the PCM for faults.
• Replace the faulty fuel pump relay.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the PCM if necessary.
• Multimeter
• OBD-II scanner
• Basic hand tools
$100 - $500
Moderate
• Ford F-150
• Ford Explorer
• Ford Mustang
• Regularly inspect and maintain the fuel system.
• Ensure proper electrical connections.
• Use quality fuel to prevent contamination.
Electrical Circuit Issue
• Have the vehicle inspected by a professional mechanic.
• Do not ignore the check engine light.
• Avoid driving the vehicle if it exhibits severe symptoms.
Check if the vehicle's warranty covers electrical components.
This code is commonly associated with Ford vehicles and often relates to relay or wiring issues.
Moderate – Address the issue soon to prevent potential engine starting problems.
Driving with a faulty fuel pump relay can lead to engine stalling, which may be dangerous.
• Vehicle in park or neutral
• Engine off
The fuel pump relay is typically located in the fuse box under the hood or inside the vehicle.
Q: Can I drive with a P1236 code?
A: It's not recommended as it may lead to engine stalling.
Q: How do I clear a P1236 code?
A: Fix the underlying issue and use an OBD-II scanner to clear the code.
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