P1399 Ford Code - Glow Plug Circuit High Side High Input
Quick Answer
The P1399 Ford code indicates a problem in the glow plug circuit on the high side with a high input signal. Common causes include Faulty glow plugs, Wiring harness issues, Corroded or loose electrical connections. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P1399 Ford indicates Glow Plug Circuit High Side High Input.
- Common causes
- Common causes include Faulty glow plugs, Wiring harness issues, Corroded or loose electrical connections.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
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Code P1399 Ford Description
The P1399 Ford code indicates a problem in the glow plug circuit on the high side with a high input signal. Glow plugs are essential components in diesel engines that help warm up the combustion chamber for easier starting in cold weather. The high side of the circuit refers to the power side of the glow plug system, where the glow plugs receive power to heat up. When the input signal is high, it means that there is excessive voltage or current flowing through the circuit, potentially causing issues with the glow plug operation.
Common Causes of P1399 Ford
- Faulty glow plugs
- Wiring harness issues
- Corroded or loose electrical connections
- Glow plug relay failure
- Engine control module (ECM) malfunction
Symptoms of P1399 Ford
- Hard starting
- Rough idling
- Engine misfires
- Decreased engine power
- Check engine light illuminated
How to Fix P1399 Ford
- Begin by inspecting the glow plugs and wiring harness for any visible damage or corrosion.
- Test the glow plugs using a multimeter to check for proper resistance.
- Check the glow plug relay for functionality and replace if necessary.
- Inspect and repair any damaged or loose electrical connections in the glow plug circuit.
- Clear the diagnostic trouble codes and test the vehicle to ensure the issue has been resolved.
Cost to Fix P1399 Ford
The cost of repairing a glow plug circuit high side high input issue can vary depending on the specific cause of the problem and the extent of the repairs needed. In general, the cost of replacing faulty glow plugs, repairing wiring harnesses, or addressing electrical issues can range from $200 to $500, including both parts and labor. However, additional costs may apply if the glow plug relay or ECM needs to be replaced. It's recommended to consult with a professional mechanic for a more accurate cost estimate based on your vehicle's make and model.
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