AEM Infinity on S52 with M50 OBD1 Cam sensor

[flexer]

Forum friends? Anyone? If I had to guess and hope that BMW matched the cam sensor then bottom pin would be 12V, middle is signal out, and top is ground.

[NOTORIOUS VR]

Forum friends? Anyone? If I had to guess and hope that BMW matched the cam sensor then bottom pin would be 12V, middle is signal out, and top is ground.

The wiring schematics have everything you need.

On the Crank Hall sensor:

Pin 1 - VCC
Pin 2 - Signal (to ECU)
Pin 3 - Sensor GND

1.jpg

[flexer]

The wiring schematics have everything you need.

On the Crank Hall sensor:

Pin 1 - VCC
Pin 2 - Signal (to ECU)
Pin 3 - Sensor GND

1.jpg

Excellent SAVE!!!

So from that the 12v supply is the middle pin, the bottom pin is the signal out, and the top pin in the ground?

Wait wait wait. How can I know what that diagram considers "top and bottom"?


Any idea the orientation of those pin numbers Notorious?

[NOTORIOUS VR]

Excellent SAVE!!!

So from that the 12v supply is the middle pin, the bottom pin is the signal out, and the top pin in the ground?

Wait wait wait. How can I know what that diagram considers "top and bottom"?


Any idea the orientation of those pin numbers Notorious?

You have to look on the plug or match the colors as labeled in the diagram

[flexer]

Sadly I have no wiring plug as previous shop must have deleted it from the harness, and I was unable to see any markings on the crank sensor itself. Anyone able to easily look at their harness and tell me the colors of the wires?

[Def]

Aren't the wire colors listed up on that wiring diagram next to the wire size (I'm guessing)? Just need to figure out BMW's color abbreviation.

[flexer]

Anyone know the abbreviations and then maybe I can find a picture of the harness and go from there?

[Def]

Usually the abbreviations are at the beginning of the electrical/wiring section of the factory service manual.

- - - Updated - - -

...and 5 secs of googling later:

https://bmwmotorcycletech.info/wires&codes.htm

[flexer]

Usually the abbreviations are at the beginning of the electrical/wiring section of the factory service manual.

- - - Updated - - -

...and 5 secs of googling later:

https://bmwmotorcycletech.info/wires&codes.htm

My man! *fist bump*

[flexer]

Can I have some help again guys? I don't have access to many of the manuals you guys do. I tried looking in the online TIS but can't find anything for a pin output description. I can see that I have the three pins going into the lower crank sensor.

AND THANKS TO YOU GUYS, I also know the colors going in are black on Pin 83, yellow on pin 48, and brown/black on pin 40.

Now I need to know which one of those is the 12v supply, ground, and the sensor output.

If anyone has an ECU pin output for a 1999 M52 US that would be excellent. NOTORIOUS VR, you posted that other picture. Does it ever give you descriptions of what those pins are?

Thanks guys

[Def]

The wiring schematics have everything you need.

On the Crank Hall sensor:

Pin 1 - VCC
Pin 2 - Signal (to ECU)
Pin 3 - Sensor GND

1.jpg

This post says it all right there. Look at the sensor pin numbers (small numbers by the wires at the sensor side), and then you know which is which.

[flexer]

This post says it all right there. Look at the sensor pin numbers (small numbers by the wires at the sensor side), and then you know which is which.

Hmm....Its just that this doesn't match any of the wiring colors on the harness I just bought. Will just roll the dice and go for it.

[Def]

The function will be pin specific on the sensor. At a minimum at least 1 pin is specified when looking at the connector on 99.999% of automatic connectors (usually they'll just list the number 1 pin, sometimes all pins are specified on the connector).

[flexer]

Ready for the conclusion?!?!?!?

Ended up being that when using the factory front crank sensor the polarity was wrong. Somehow in AEM's software it didn't like what it saw so while it would show the cam sensor dropping, the cam sensor wasn't actually dropping, it would just reseting it.

Took a while to get someone at AEM that could explain what I was seeing. Flipped the + and - VR wire and BOOM, car fired right up.

[Def]

The Infinity wants to see a rising pulse from 0V on the cam sync trigger. I think the Infinity documentation even mentions this is a requirement.

[flexer]

The Infinity wants to see a rising pulse from 0V on the cam sync trigger. I think the Infinity documentation even mentions this is a requirement.

Yes. I would have gone immediately after that if it wasn't for being told by a AEM tech that the cam sensor was the issue and that you could clearly see the signal falling out in the log.

I just got bad info that was leading me to go down a path that was a complete waste of time.

All good though. Got it. Hopefully my thread here helps out someone in the future.

[flexer]

ANOTHER QUESTION to my infinity users:

The 3 wire BMW IACV. What are you guys doing there? The AEM V1 and V2 box could control a 3 wire IACV, but the infinity can only do a 2 wire PWM or a 4 wire stepper.

Is there a work around?

Thanks for the help

[NOTORIOUS VR]

Is there a work around?

Yes. Look at the PnP User manual for the E36 Infinity.

It tells you what to do.

[Def]

ANOTHER QUESTION to my infinity users:

The 3 wire BMW IACV. What are you guys doing there? The AEM V1 and V2 box could control a 3 wire IACV, but the infinity can only do a 2 wire PWM or a 4 wire stepper.

Is there a work around?

Thanks for the help

The AEM Infinity easily controls a 3 wire PWM idle control valve just like a factory ECU. I'm running my 3 wire 3S-GTE IACV this way. You just flip the output for the "close" pin versus the "open" pin.

I posted this on the AEM forums just to make sure I wasn't missing something and the software would flip out, but it works just fine.

https://www.aemelectronics.com/forum...owside-outputs


You can either build a flip-flop circuit to get back a LS output, or just pull the closed pin always closed via a resistor pulled up to 12V.

[murad5058916]

You should get the (m50 vanos) camshaft sensor
Wires
1)b+
2)cam signal to the ecu
3)ground-5v