Kessy Open Circuit

[JonnySommes]

About 8 months ago the keyless defective on my MFI came on in my 2012 GTI. After replacing the battery in the fob and troubleshooting different things, I made sure the wire to the antenna located behind the rear seats was properly connected. It was but I suspected that the wire was pinched under the seats so I smoothed it out and jostled the cable a bit and sure enough it worked. Kessy worked fine until a month ago. That’s when the Kessy on the driver door started to intermittently not work and eventually stop working completely. It threw DTC B116B13 (driver exterior door handle touch sensor open circuit) and B116F13 (driver Access/start system antenna - open circuit). All the while, Kessy on the passenger door worked until a few days ago. Up until then the keyless defective message came up sporadically but now it’s all the time.
I did a quick visual inspection of the loom and it looks fine. No visible sign of water damage. I rechecked the wire harness to the antenna behind the seats and found some fraying on the black wire. I was wondering if this could be the reason for my Kessy problems and any suggestions on how to fix it?

Thanks so much!

 

[GolNat]

Can you see exposed wire through the insulation? I’d put some electrical tape on it for sure.

 

[JonnySommes]

No exposed wire so I put electrical tape and it fixed the issue with the passenger door and I no longer see the message on the MFI but Kessy isn't working on the driver door. I removed the driver side door handle and wires look pretty clean and no sign of tearing. What am I missing?

 

[GolNat]

Maybe try cleaning it?

Check the wires/loom at the door jamb. Over time from opening and closing the door the wires can become brittle or get frays in them.

 

[JonnySommes]

Already looked at the wires/loom. Didn't notice anything particularly bad. How do you suggest cleaning it? Would something like Deoxit D5 Spray work? Would a VCDS tell me exactly where the problem is?

Thanks for all of your help!

 

[GolNat]

The bad part might be in the rubber groomet part where it bends. Can you take the rubber off completely without cutting it?

Pull the connector out and I would use something like contact cleaner on it. Not sure if VCDS would help but if you have it I would certainly hook it up and see. I believe you can use it to look at inputs and outputs so you might be able to narrow it down to what input/output you are missing.

 

[JonnySommes]

I think I can take the rubber grommet off. I'll need to look. Are you thinking to replace it or see if there's a damaged wire underneath it? I'll have a look when I clean it and apply contact spray

I don't own a VCDS but I stopped by a mechanic and it read:
1052939 - Touch Sensor on Exterior Door Grip, Driver Side
B116B 13 [009] - Open Circuit

Any suggestions? Thanks again

 

[GolNat]

See if there is a damaged wire underneath.

The actual sensor might be bad then. Maybe see if you can tell what wires go to the sensor and try ohming them out. If you can’t tell what wire ohm out various wire combos on the passenger door and compare the readings to the driver door. You might just need a new door handle (if you can’t just swap the sensor).

 

[JonnySommes]

I'm going to start with cleaning the connector and inspecting for any damage. ECS sells this connector which connects to the handle. https://www.ecstuning.com/b-genuine-volkswagen-audi-parts/housing/3c0973704/

Is this what you're suggesting replacing? I believe the sensor is in the handle itself and cannot be replaced. You just get a new handle.

 

[GolNat]

No I was suggesting replacing the sensor, so getting a new handle.

You could maybe swap the handle from the passenger side to see if the code clears.

 

[JonnySommes]

I cleaned the connectors and still no luck. I'll try homing when I have more time but I think I'm going to need to get a new handle. Bummer.

 

[JonnySommes]

See if there is a damaged wire underneath.

The actual sensor might be bad then. Maybe see if you can tell what wires go to the sensor and try ohming them out. If you can’t tell what wire ohm out various wire combos on the passenger door and compare the readings to the driver door. You might just need a new door handle (if you can’t just swap the sensor).

Before I go buying a new handle and painting it, I figured I should at least test the wiring but was wondering if you could explain how one ohms wires? The connector (https://www.ecstuning.com/b-genuine-volkswagen-audi-parts/housing/3c0973704/) has four wires going into it and the handle with 4 number pins (photo attached) plugs into it. How do I test each one? Is there a way to lookup what the value should approximately be without removing the passenger door handle? It requires a specific tool that I don’t own.
Thanks for all your help!

 

[GolNat]

You might be able to look up the values in a shop manual. Without a manual your best bet is to compare it to the passenger side. Compare various ohm readings of the door handle side.

For example;

Pin 1-2
Pin 1-3
Pin 1-4
Pin 2-3
Pin 2-4

Let’s say you get .5 ohm reading between Pin1-4 on the passenger door but it’s OL or open on the driver door then that might be your open circuit code that you are getting.

You might need to get a paper clip to get into the connector. Be very careful poking around on the car side of the connector as there is probably 12V positive and you could short something out. Disconnect the battery to be safe. I would check for power going to the handle, negative on chassis and positive lead to Pin 1, then Pin 2, Pin 3, Pin 4.

 

[JonnySommes]

You might be able to look up the values in a shop manual. Without a manual your best bet is to compare it to the passenger side. Compare various ohm readings of the door handle side.

For example;

Pin 1-2
Pin 1-3
Pin 1-4
Pin 2-3
Pin 2-4

Let’s say you get .5 ohm reading between Pin1-4 on the passenger door but it’s OL or open on the driver door then that might be your open circuit code that you are getting.

You might need to get a paper clip to get into the connector. Be very careful poking around on the car side of the connector as there is probably 12V positive and you could short something out. Disconnect the battery to be safe. I would check for power going to the handle, negative on chassis and positive lead to Pin 1, then Pin 2, Pin 3, Pin 4.

Yeah, that actually makes complete sense. I think it probably makes sense to test the handle first as then I'll know if it needs to be replaced. The Humble Mechanic actually suggests doing a drop voltage test and it makes sense why that's preferable.

I was checking out an Audi blog and there was a similar inquiry. I'm apparently looking for 11-14 DC. Does that sound right?
https://www.audiworld.com/forums/a8...0/testing-see-if-kessy-getting-power-2897751/

Thanks for all of your help

 

[GolNat]

Yep 11-14 VDC is where it should be.

Charles is more referring to checking the actual wire (from the short clip I watched) which is correct. I was suggesting just ohming out the switch. You could do a voltage drop test at the door latch compared to other points in the circuit (door jamb connection, fuse box, battery).