Earlier today I went out to look at a 2003 Focus, as per title, that had suffered a period of total power loss on the motorway, no DTC's logged, and no seriously odd points to report - atleast not in as far as a visual inspection was concerned.
I was asked to concentrate my efforts on the electrical side, as the owner has a mechanic friend who would be looking at the car after me.
I have been completely unable to force the fault, or even have it present while I was there, the owner said it wouldn't even idle during the fault period.
I took a look at the MAP output, and have added the psdata file. My question is what is the actvity on channel A?
CHB appears to be an anologue output, and CHC is power at +5v. The sensor is a 4 wire unit, with the remaining wire being ground and not covered in the attached waveform.
The 'blip' is when I revved the car up. Wiring diagrams show the blue trace & red trace both as ECU inputs.
Can anybody describe the principal of operation of this sensor, and outline what the blue trace is doing?
- FOCUS 1.6 ZETEC SE MAP SENSOR, ODD.psdata
- (1.42 MiB) Downloaded 237 times