P1128 1997 FORD F150 Possible Causes
- Crossed HO2S harness connectors
- Powertrain Control Module (PCM) harness connector
How to Fix P1128 1997 FORD F150 Code?
Start by checking the “possible causes” listed above. Visually inspect the corresponding cable harness and connectors. Check for damaged components and look for broken, bent, pushed, or corroded connector pins.
Possible Symptoms
- Check Engine Light on (or engine warning light soon to come on)
P1128 1997 FORD F150 Meaning
The Diagnostic Trouble Code (DTC) will set whenever the Powertrain Control Module (PCM) detects the upstream oxygen sensor is swapped from Bank to Bank. The Heated Exhaust Gas Oxygen (HEGO) sensor monitor checks and determines if the HO2S signal response for fuel change matches the correct engine bank. The code sets when the HO2S being tested is not indicated.