Ford DTC P1128 – Heated Oxygen Sensor Signals reversed
DTC P1128 meaning on Ford
DTC P1128 on a Ford vehicle indicates that the heated oxygen sensor (HO2S) signals are reversed for bank 1 sensor 1. This means that the oxygen sensor is sending incorrect signals to the engine control module (ECM), causing potential issues with fuel mixture control.
Ford DTC P1128 symptoms
Symptoms of DTC P1128 on a Ford may include:
- Check Engine Light (CEL) illuminated
- Poor fuel economy
- Engine running rough or misfiring
- Reduced engine performance
Ford DTC P1128 causes
Common causes of DTC P1128 on a Ford include:
- Faulty heated oxygen sensor (bank 1 sensor 1)
- Wiring or connector issues in the oxygen sensor circuit
- ECM software or hardware problems
Ford DTC P1128 seriousness
DTC P1128 should be addressed promptly as it can lead to poor engine performance and reduced fuel efficiency. Ignoring this issue may cause further damage to the engine or emissions system over time.
How to diagnose DTC P1128 on Ford
To diagnose DTC P1128 on a Ford, you can:
- Use a scan tool to retrieve the trouble codes and freeze frame data
- Inspect the wiring and connectors related to the bank 1 sensor 1 oxygen sensor
- Perform a visual inspection of the oxygen sensor for any physical damage
- Test the oxygen sensor using a multimeter or oscilloscope
How to fix DTC P1128 on Ford
To fix DTC P1128 on a Ford, you may need to:
- Replace the bank 1 sensor 1 heated oxygen sensor
- Repair any damaged wiring or connectors in the oxygen sensor circuit
- Update the ECM software if necessary
How to erase DTC P1128 on Ford
To erase DTC P1128 on a Ford, you can:
- Use a scan tool to clear the trouble codes
- After making any necessary repairs, drive the vehicle to allow the ECM to perform a self-check and verify the issue is resolved
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