M52B28 INPA Code 65 - Camshaft Position Sensor - Faulty wiring harness?

[jsta1109]

Desperate plea for help,

I replaced my cam sensor on my single vanos m52b28 with an aftermarket sensor as it was the only one I could get on the day. My original one had lost all its insulation due to contamination. Under INPA that sensor threw a code 65, so upon doing research I discovered people have issues with aftermarket ones out the box. Cool, I replaced it with a BMW dealer part brand new in box, it's still throwing the same code.

Under both sensors my cam position was reading 80degrees kw or quite advanced (which is obviously wrong). I pulled the VC off and inspected the cams in case there was incorrect timing physically, that all checked out. Currently I am running a seimens MS41.0, as far as I can tell the harness and DME are fine, the physical cams are fine, and I am sure a brand new dealer part wouldn't fail.

[328ijunkie]

Why are you running ms41.0?
I've seen bad insulation fry 5v driver in DME..

[jsta1109]

All Australian M52s run MS41.0, we got the semi OBD2 cars. I know the recall on crank sensors wasn't a thing on front crank sensors (correct me if I'm wrong) so we still run the 5v signal wires for both and no piggy back harness on the vanos solenoid.

[NotJesus]

I've seen bad insulation fry 5v driver in DME..

+1
Have you tried installing a known working dme to see if that may be your issue? Also, you can continuity check the wiring harness by finding a pin diagram for the dme (ecu) plug and continuity testing between the pin on the dme plug and harness side plug for the cam position sensor. It would be simple to do a resistance test also, so you can be sure the issue isn't your harness, I'm guessing it's the driver in the dme though.

[jsta1109]

Currently tried 2 dmes, all I've done on both is flash ews off, error persists on either. I'm going to try get a third and see if it still persists

Continuity has been checked and is fine

[ba114]

Have you checked the harness thoroughly? What do you mean by you've checked continuity?

Unplug sensor. Check pin 3 of the harness plug for continuity to ground. If this is constant, you will throw the DTC.

[jsta1109]

Update -

Checked voltages on some of the 5v supply straight off the back of the ecu plug, referencing M52 328i ETM I am getting voltage (1.8v roughly) on pin 42 (tps ground), voltage on pin 44 (2.4v on TPS output), pin 64 shows 2.4v (camshaft position ground) and pin 65 is showing nothing.

Appears as if there's some kind of short or poor ground somewhere that I am unsure of. Flipside I get 5v on the supply for crankshaft sensor?

[jsta1109]

Update in case anyone ever winds up here chasing a similar fault. In the end I purchased another Cam Sensor, after diagnosing all other points with a BMW tech. This new cam sensor plugged in, no more codes, correct cam reading, car drives really well with no other issues. Apparently it is fairly common for cam sensors (even VDO/Genuine ones) to be faulty out the box.

[Klug]

I had the same issue- swapped in a new cam sensor and all my codes went away

[jsta1109]

Thing is, after you replace it three times, you start to question whether a fourth one will fix it. In the end I now know better than to just assume that a particular part is functioning properly, even if it is new.

[Klug]

Back from the dead!

Jsta1109- was the 4th time a charm?

I'm getting the same issue again, even after replacing the sensor the 1st time back earlier last year. Drove about 1200 miles on it and now it is acting up the same way again. Purchased another new Myle sensor- swapped it in- nothing. Going to try this again....and just go the OEM route.

s52 runs fine, but I can tell it is a bit 'off' with its idle and acceleration.

[jsta1109]

Back from the dead!

Jsta1109- was the 4th time a charm?

I'm getting the same issue again, even after replacing the sensor the 1st time back earlier last year. Drove about 1200 miles on it and now it is acting up the same way again. Purchased another new Myle sensor- swapped it in- nothing. Going to try this again....and just go the OEM route.

s52 runs fine, but I can tell it is a bit 'off' with its idle and acceleration.

4th time was the charm, thus far no more issues (roughly 5000ks/2500 miles). I replaced it with an OEM unit, had no luck with any aftermarket counter parts.

Without a proper/working cam sensor mine was struggling to start (needed throttle or it would stall, would idle once it started though), you could hear the injectors batch firing (sounds like lifter tick) and was noticeably down on power in the lower range, I assume it was down up top as well but it was hard to tell.

[Klug]

Thanks jsta1109-

I should have known, I know with non-OEM m20 Crank PS, the only one that works is OEM. I just purchased an OEM one yesterday for double the price- hopefully this one will work correctly. Damn these finicky sensors!