Replacing the crank reference sensor
 

I'm completing a light refurb on my C4. One of the items I found in my engine drop is a heat affected crank ref sensor plug, where the sensor side literally crumbled. Rather than rebuild the plugs (part of the plug is fused in the receptacle) I ordered all new parts.

The newer sensor is a 996 part with a different plug, so the harness connector side must be changed as well.

Parts needed are:

996-606-105-00 [sensor]
999-652-916-49 [plug]
999-652-871-22 [connector]
999-704-161-40 [grommet]

This bulletin was put out by Porsche. And the Wiring manual agrees with the colour

The plug has numbers on it. So 1 is White, 2 is Brown and 3 is shielding. Seems pretty simple (if Pelican had sent me the right connectors grrr)

However the wires on my old sensor appear to be White and Black not White and Brown. I assume that's just a manufacturing change, or is it? I get the body back this week and can look at the Harness then. In the meantime has anyone done this and found a similar colour difference?

Btw the new sensor is a direct fit and as it's the same length as the old one I haven't adjusted the gap.

Why wouldn't you backdate the plug on the sensor side rather than messing with the car's harness? Are the 964-era OE style connector parts still available?

Are shims used to set gap?

The gap should be 1mm +\- 0.2mm. I image a feeler gauge would work although access is not easy even with the engine out of the car as the transmission case is close to it.

I believe they are AMP connectors and parts are available. As the male plug fused inside the female plug I needed to do two and even then I'm not sure why it fused in the first place. I thought it was best to start clean because replacing the sensor is easy when the engine is out.

Hi John,
How did this end up?

was the color coding correct for your installation?

Here is the harness connector I'm going to cut out to replace with the new oval connector.
Attachment 1356837

New parts:
Attachment 1356838

Since I'm doing this very same thing today and wanted to know how it turned out.

Thanks!

It worked fine. Car idles and revs correctly so it's getting the right signal to the ECU.

Did you tin the wires or solder them at all?

Thanks again!

Because Pelican Parts supplied the wrong pins I reused the existing ones in the connector. Not perfect but it seems to be working ok. FWiW I always solder where I can.

I finished installing this but I'm not sure I was successful.

I'm satisfied with the quality of my assembly of the cable connector, but when I crank the motor it still doesn't start. The tachometer needle doesn't move when cranking.

Does this mean I need to take a closer look at the connector I just put together?

Pin1 = white
Pin2 = brown
Pin3 = shielded

I did feel the connectors 'click' when pushing them into the housing. Nothing too difficult in putting it together. Is it possible 3 and 1 should be switched?

Problem is after putting it tougher, it doesn't seem like you can take it apart without destroying it.

Thoughts?

Just took some pics of my connector. Are you sure the plugs and wires are correct? Did you set the gap for the sensor as per specs?