ingybing

Hi all,

I've recently had a PDC failure, started as one sensor not clicking then everything has gone front and back. I've started pulling out the boot trim to take a look and found my battery well full of water and the spare wheel bowl as well.. \o/ yey, lucky me. So waters been getting in and has soaked the PDC cables and connector blocks. I've got rid of the water, dried things out and will go leak hunting later but for now i'm trying to get PDC up and running again. I've hooked it up to INPA which is reporting a Short to Negative on all wires front left, left center, right center, right etc and all back sensors. Theres some corrosion that's formed around the pins to the controller and in the connector blocks by the look of things... Does anyone have any helpful suggestions about how i can pin down this 'short to negative'.

I've had the controller apart and can't see anything visually in there thats bridging pins etc so think i may be the connector blocks.. Does anyone know if these can be disassembled / cleaned out incase it's something in those? Other tips... Here's a picture of the cable i'm talking about.

ingybing

Looks like pin 8 on module one connection has corroded and snapped off in the block. Going to try move the wire from pin 8 to pin 7 and then bridging pin 7&8 on the board. Pin 7 appears to have no track. I'll update later if this works.

Worked out how to get the block out of the clamp connector. Put the arm into the release position and the left the little tab on the side of the block / clamp housing and push the inner block through the hole in the other end.

tonyb635

There is a procedure on here to relocate your electronic modules from your wheel well over to the left side. If all you have is a pdc issue you are VERY lucky. That issue can cost you thousands of dinaro! Most likely the source is your sunroof drains are clogged.

ingybing

PDC was the only controller in the spare wheel bowl thankfully... *phew*.. As for the leak, i've not got a sunroof so presume no drains or are these present in the absence of a sunroof?

tonyb635

I would agree if no sun roof then no drains. There are a few more areas such as the trunk vents which are behind your battery area I believe, trunk seal etc...

ingybing

I've moved the pin 8 wire in the block to pin 7 and the bridge the connections on the board to join pin 7 onto 8... still no joy. DIS is still reporting all sensor connections have a short to negative. Next step is going to be ripping off the rear bumper trim and having a look wiring harness & connections... and if that turns up nothing then eventually i'll have to try replacing the PDC controller, when i've got some spare cash to give to the stealers to re-program. Why oh why can't you just make your modules plug and play BMW and don't give me anti theft rubbish

Did find this which might be helpful to someone else messing with PDC wiring...

Construction
The PDC control unit is connected to the rest of the vehicle electrical system by 3 plug connectors.

Pin assignment for X300, 12-pin
Pin Type Description
1 V Power supply, terminal 15 - For vehicles from 03/2004: terminal 30g (active)
2 E/A CAN high on K-CAN
3 --- ---
4 --- ---
5 --- ---
6 M Earth, terminal 31
7 --- ---
8 E/A CAN low on K-CAN
9 --- ---
10 --- ---
11 --- ---
12 --- ---

E/A = Input and output M = Earth
V = Supply




Pin assignment for X18013, 18-pin
Pin Type Description
1 A Earth for ultrasonic sensor, rear right
2 A Earth for ultrasonic sensor, rear left
3 --- ---
4 --- ---
5 A Power supply for ultrasonic sensor, rear middle right
6 A Power supply for ultrasonic sensor, rear middle left
7 A Power supply for ultrasonic sensor, rear right
8 A Power supply for ultrasonic sensor, rear left
9 --- ---
10 A Earth for ultrasonic sensor, rear middle right
11 A Earth for ultrasonic sensor, rear middle left
12 E Signal from ultrasonic sensor, rear middle right
13 E Signal from ultrasonic sensor, rear middle left
14 E Signal from ultrasonic sensor, rear right
15 E Signal from ultrasonic sensor, rear left
16 --- ---
17 --- ---
18 --- ---
A = Output
E = Input
For current specifications regarding pin assignment, please refer to BMW diagnosis system



Pin assignment for X18362, 18-pin
Pin Type Description
1 A Earth for ultrasonic sensor, front right
2 A Earth for ultrasonic sensor, front left
3 --- ---
4 --- ---
5 A Power supply for ultrasonic sensor, front middle right
6 A Power supply for ultrasonic sensor, front middle left
7 A Power supply for ultrasonic sensor, front right
8 A Power supply for ultrasonic sensor, front left
9 --- ---
10 A Earth for ultrasonic sensor, front middle right
11 A Earth for ultrasonic sensor, front middle left
12 E Signal from ultrasonic sensor, front middle right
13 E Signal from ultrasonic sensor, front middle left
14 E Signal from ultrasonic sensor, front right
15 E Signal from ultrasonic sensor, front left
16 --- ---
17 --- ---
18 --- ---

A = Output
E = Input
For current specifications regarding pin assignment, please refer to BMW diagnosis system

ingybing

In the end, replaced the PDC controller. Got a part from a breakers on ebay.. replaced mine which was part number:66 21 9 978 232 with one of EBay for £69 which was Part Number: 66 21 9 185 139.

Just plugged in the replacement and it all started working again. No coding required even though TIS said the replacement would need coding.

TIP:
I did find out that if you unplug module 1 (the smallest block) and plug it in again the unit does a quick test of the sensors so you should hear them click as soon as you plug it in for a couple of seconds. This may help you tell if the controller is dead.