[DIY] Polo 6C Headlight Washer Retrofit

[iichel]

The sensor itself is indeed higher up in the tank. It's been around since the mk4 golf. I think I was still in diapers by then...

[Eduard]

Hei RUM4NO. I'm going to work on it later today, and post here the results. Basically the harness is correct, only the terminal for the washer pump doesn't exactly fit, but I've replaced that one. It's just the wire numbers on the relay which are wrong, as well as the wire colors ( since it's for a 6R ) but we got that sorted, then:

1. 30 AMP Fuse goes into C-Fuse holder slot 11
2. Relay into slot 7 ( D-fuse holder ) -- have to figure out how to get access to that relay carrier and how to stick the relay in .. as they seem to have some kind of a grip thingy.
3. Gray wire from fuse to relay into pin 3
4. GND from relay and GND from harness to the closest stud
5. Yellow wire from relay to T46b/34
6. Red/white wire from harness goes into the relay
7. Purple wire to T46B/14 ( washer fluid level )
8. Connect the two terminals, one into the washer fluid sensor and second one to the headlight washer pump

Open VCDS, Instrument cluster ( activate washer fluid level warning ), then probably 09 - central electrics and look out to activate the headlight washer system ... not sure where that is, will have to find out.

And I think we're done ... iichel, correct me if i'm wrong, but I think this is the way. Will just have to try and see if it works.

[iichel]

I didn't check in detail but globally it sounds good. I trust you did your homework well and asked the right questions

[Eduard]

Guys .. quick... is there easy access to the bcm and the relay carrier ? Do i need to get this foot panel out ? If so, how ?

[RUM4MO]

The sensor itself is indeed higher up in the tank. It's been around since the mk4 golf. I think I was still in diapers by then...

No No No I was talking about the pump being mounted higher not the fluid level sensor - some bad person changed the connector type so when I replaced my Passat pump in around 2008, I had to fit a new mating power connector, original pump has a section of exposed metalwork which seemed to catch any passing water blown into the engine bay, that lead to the metalwork rusting and that means it expanded and cracked the pump casing meaning the motor eventually seized. I think that the later Swiss made pumps were modified versions.

[RUM4MO]

Guys .. quick... is there easy access to the bcm and the relay carrier ? Do i need to get this foot panel out ? If so, how ?

Sorry not been in there yet! I'd think that the panel will need to get removed though so that you can reach in to the relay carrier area and the BCM.

[Eduard]

Crap. Slot 17 in the instrument cluster is already there with something in. Iichel, do you have a pic with the diagram ? Can’t search the pdf on mobile..

EDIT: iichel I tend to deny your affirmation regarding the washer fluid level sensor just serving for the warning lamp in the cluster. While I tried the retrofit today, I unscrewed the cluster thinking it just goes into pin 17 ... ( after looking at a 6R retrofit ) ... which is wrong for 6C.

Fluid level sensor goes into T46b/14 so it's actually going into the BCM. This makes me think it is ( or could ) be used for something more than just the warning lamp, as RUM4NO stated.

Think BCM look at headlight status ( on ) + washer level sensor ( enough ) + few windscreen washes in between headlight washes ( maybe ? ).

[iichel]

I'm very sure the function of the washers will not depend on the low level of fluid. There is no harm in the pumps running without fluid, but non-operation of the pumps might be dangerous for visibility or light pattern.

I've seen the low level warning light a few times, but the pump never stopped working. Once it was actually empty and the other time the wire escaped from the therminal.

Many of the sensors, that used to go into the 6R instrument cluster, now go into the bcm too. I'm not exactly sure which ones since I don't have an Elsa with me, but it's sensors like the ambient temperature sensor, fuel level sensor, handbrake sensor, brake fluid level sensor, brake pad wear sensor.

[Eduard]

Ok, understood all the wiring is added, just need to find out a part number of the relay bracket, so i can buy one for the current relay and do the actual coding.

Will see what happens afterwards, waiting on the bumper from paint shop, then i will fix the first post with the pictures. Hope all is good

[pipsyp]

Sorry guys, I cant help with wiring but I can help with the reason behind the level sensor with headlamp washers.

When the low level is triggered it does (certainly on all the factory spec'd VAG cars ive had) disable the headlamp washers as its not good for the high pressure pumps to run without fluid. It does also serve to preserve fluid for the windscreen until you fill up but protection of the pump motor is the main reason.

I have found you can find yourself right between the level where the warning is triggered....so the warning comes in and off until youve used a bit more fluid....but once its on permanenly the headlamp washers shouldnt activate until the fluids topped up.

[Eduard]

OK gents. So, I'm now done with my vacation, HEX-NET arrived about a week ago, finally, and the 7M0973202 connector ( for the fluid level ) has now arrived as well.

My questionn is, as it would be the first time I'm dealing with wiring and stuff, where exactly am I supposed to pull the new wires through, to get from the engine bay area to the fuse holder under the wheel ? LHD here

Anybody has any sketch or pictures ? Been lurking around the engine, but I couldn't figure it out.

Please advise

[ciclo]

viewtopic.php?f=56&t=69648&start=15#p519846



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4H0937529

viewtopic.php?f=10&t=42713#p466570

[Eduard]

Thanks for the reply! Also thanks for the relay socket PN Will fiddle with it today, and come back with some results ( hopefully )

[Eduard]

Hello guys!

First, I would like thank you all for the valuable information and for the knowledge I've acquired meanwhile working on this.

Secondly, I'd like to say that the washer fluid level sender works just fine after wiring and making the setting for it.


Third in hand, I'm yet to figure out why the headlight washer system is refusing to start. So, there goes some troubleshooting I've done.

1. I've swapped out the connector from the windscreen towards the headlight washer pump, and it works just fine, which excludes hardware issues.
2. Double checked the wiring from the pump to the relay, and the T46b BCM plug, as follows:
-- GND from PUMP to earth connection
-- Wire from PUMP to RELAY ( PIN 5 )
-- 30 AMP SC11 wired to RELAY ( PIN 3 )
-- Wire from T46b/34 to RELAY ( PIN 1 )
-- GND from RELAY ( PIN 2 ) to earth connection

3. Did the VCDS setting, in 09 - Central Electronics, Byte 13, Bit 3, Headlight washer system, installed

4. Ran an autoscan, returned no errors. Is there any method in VCDS to check if it is installed correctly, or do I just assume it is, given there are no errors in the autoscan.

Now, I know there are some conditions to be met in order for the jet washers to start when cleaning up your windscreen, as follows:
a) Headlights must be on
b) Enough washer fluid ( no washer fluid warning )
c) Wash must last longer than 3 seconds ( i think )
d) It only happens once 5 or 6 windscreen washers ( according to RUM4NO , for some cars only )

So I've started the car, left the engine idle, switched to low beams ( even got high beams on ), tried washing the screen a few times, for more than 3 secodns each time, nothing.

It seems like the BCM does not trigger the relay whatsoever. Will try and put in another fuse, with a new relay, maybe something's wrong there.

Any ideas ?

[iichel]

check the relay, check the ground connection, check the BCM connector...