J59 Load Reduction Relay!

[Aronis]

Hello!

I have achieved greater understanding of the Bentley Manual Wire diagrams! LOL.

My headlights, turn signals, wipers, and fog lights went out again. I could smell something burning when I got to work, and when I got back in the car to go home these items were out.

The last time it was a short between two wires in the connector to the headlight switch. I fixed that. All was fine with that for a few weeks. (the other "fuse" and no volt meter and battery light is another thing).

I checked the connector again and there was no short. The fuses for those systems are ok.

I figured out which wire is which in the headlight switch connector, and determined the wire that was shorted before was not the ground as I assumed, but a positive coming off the J59 load reduction relay (pin 1/ Xz) shorted to the power going to the fog lights (pin 2/Xr). So now those two have no power with the car running. There was only power at pin 15/30 which is a direct connection to the positive terminal and from the diagram provides power to the parking lights (and all four parking lights light up fine).

So it appears that the relay which has been clicking too much over the past year may very well have been a failing load reduction relay and now those systems are out.

The thing I could not figure out from the diagrams is how the windshield washer fits into this. I will have to look at that diagram for a little while longer to see where they connect, but I cannot determine the positive power input to that circuit (yet) and suspect it too comes from the J59 relay.

Going to open up the dash and pull that relay and replace. Looks like a $10 part.

Mike

[Aronis]

Ordered part.

8D0 951 253

apparently superceded by part number

4H0 951 253

$6.73 at partsgeek (plus shipping 3 to 4 days) vs
$33.53 at VW dealer (who will have it tomorrow LOL).

Mike

[hahnmgh63]

Let us know where the partsgeek relay is made. Sometimes cheap really means cheap (made in China). I bought a Bosch Crankshaft Position sensor and it was made in China, returned it as I found another Bosch CPS that was made in Romania so I took that over the Chinese one. Too many Chinese junk stories out there. And I didn't want to go back in there changing the CPS. OEM was fine btw, just installed the shorter 6spd one to work with the flywheel.

[Aronis]

no, I got one from Audi....I know better.

It's at the dealer now, if I can pick it up today, I'll plug it in.

If that does not work, then the car is going to the crusher.

Mike

[Aronis]

Replaced relay, no dice. Checked power at the hot side of the relay and it is there.

I cannot figure out what circuit in the car tells that relay to close.

Any ideas?

Mike

[Aronis]

Here is what I have figured out from the wire diagrams.

E1 is the parking lights switch. Fed by (3) via pin 15/30 which is Hot from Pin 30 Red Plus (hot from battery), it feeds to (50) which goes to left tail light and left parking light and (34) goes to right tail light and right parking light.

These work.

E23 is the headlight switch. Fed by Yellow/black wire (1/XZ) which comes from the Relay J59. This relay is open at this time. There is power at it's hot side of J59, but not after. I do not yet know what turns this relay on and off. It's called Load Reduction Relay.

E23 also manages the fog lights and it's output is to pin 2/XR of that connector (next to 1/Xz), and feeds through a fuse and into the E4 Headlight dimmer/flasher switch to feed the high beams and turns fogs off when hi's are on. It also feed J5, fog light relay and the rear fogs. These do not work.

So the parking lights work but the Headlights, turn signal, fog lights and wipers do not. The Hi-beams do work ONLY WITH FLASH switch pulled back, not with switch pushed forward to the regular hi-beam on position.

I need to take a fresh look tomorrow when not on call and can concentrate. I have checked fuses but need to methodically check them all again.

I'll note which systems work. Radio. A/C/heat blower. Heat and defrost. Rear window defrost. I cannot confirm A/C is working since it's too cold outside. Interior lights work, hi beams work with Flash, but not on position check, glove box light works and turns off with head light switch turned off (as it should).

I do not yet know how this related to the other issue of the Volt meter not working, "Fuse" warning for Fuse 15 being out, and the Battery Symbol in the display. My new battery has been fine for more than a month.



1842518426

[nubcake]

This relay clicks over when you engage the starter, cutting power to a bunch of "unnecessary" systems.
Off the top of my head - signal should be coming from the ignition switch itself. I'm not sure.

[Aronis]

This relay clicks over when you engage the starter, cutting power to a bunch of "unnecessary" systems.
Off the top of my head - signal should be coming from the ignition switch itself. I'm not sure.

That is what I think also!

Doing VagCom Scan now.

Mike

[Aronis]

1842718428184291843018431


more info....

Looking at the J59 relay diagrams and comparing to physical findings in car.

Physically in car: The four pins are labeled on the actual relay (1) 86, (2) 85, (3) 30, and (5) 87. When I check with my ohm meter I have continuity from pin (2)85 to the Yellow/Brown wire which goes to the headlight switch (1/Xz) and continuity to ground from pin (1) 86. Pin (3) 30 is hot 12v/14v. Pin (5) 87 is the control input. I carefully translated which pin is which known that the relay is flipped over when I look at the back of it. It appears the Bentley manual wire diagram has pin (1) 86 and pin (2) 85 reversed.

On Wire Diagram:

J59 - pin labeled 8/85 connects to line 31 (there are labels for 30, 15, X and 31 as well as 75 but note this internal 75 line is NOT included in the other J59 diagram I up loaded as this wire diagram shows up in several different parts of the bentley manual). If you follow "internal line 31" this goes to ground at ground connection 81 in the instrument panel ground. ( But physically in the car this line goes to the headlight switch)
- pin labeled 5/86 goes to the yellow/brown wire (ge/sw) going to the ignition switch and to the head light switch. (not through the ignition switch). (But Note physically in the car this item labeled 5/86 actually corresponds to the port at the J59 mounting site that goes to GROUND when I use the ohm meter.) This line 5/86 also goes to internal line 75 and when I follow that on the internal bus it goes to the Horn Relay - thus why the horn also does not work LOL)
- pin labeled 7/30 goes to internal line 30 which goes to plus 12/14v. This tests out on the physical jack site as pin 7 is hot.
- pin labeled 6/87 goes to internal line "X" which I ASSUME (ass out of you and me) goes to the control system which turns the relay on and off.

So from physical evidence I think the plug sites labeled 5 and 8 are actually flipped in the manual.

Here is my plan......tell me what you think. I am going to get an inline fuse with heavy wire and jump between the hot line (socket 7, ie pin (3) 30) to the line going to the headlight switch (2)85 socket labeled 8) and see if my headlights, turn signals etc work again. If I have the connections backwards (ie the labels are correct) I'll just blow that inline fuse to ground. If I have it correct there will be power at the 1/Xz pin on the headlight switch and thus the lights will work.

Mike

[Aronis]

With jumper wire in place, the headlights, hi beams and horn work.

Turn signal and wipers to not.

Progress I guess.

Looks like the ignition switch may be the cause.

Mike

[Aronis]

I traced everything back to the ignition switch. It appears to be the problem, new part is on the way.

Mike

[Aronis]

Ignition switch replaced! BINGO!

Headlights, wipers, horn, turn signals back on!

YA!


Mike

[P1054]

Awesome! Glad to hear you got it solved.

[Aronis]

New info on the interior light dimmer and the fuse 15 short!

I spoke with an Audi mechanic and service manager whom I have both know for more than 10 years (they have worked on my car several times when I still was under warrantee).

The tech said that the interior light dimming is done via the instrument cluster circuitry as directed by the rheostat, and not by just the rheostat per say. So this explains the sequence of events, first I intermittently lost dimming ability, then it went out completely, then the error in the display presented along with the fuse 15 short to ground.

Next step is to remove the instrument cluster, unplug it and see if that short resolves. The part is available from Germany, $950 plus tax and shipping and requires dealer coding, so probably $20grand additional in service fees. But I am going to go to my local mechanic where I get my cars inspected each year and figure out if the car will pass inspection as is. Then I'll just leave the blown circuit as is.

Mike

[Aronis]

18458


Now the bentley manual makes sense. The dash light dimmer switch only connects to an input on the J285 (instrument cluster) and no other wires apparently leave it!.

Part of the interior lights are fed from pin T32/20 58s of J285 the output is distributed to the various lights in the car, emergency flasher switch backlight, cigarette lighter backlights, fog light switch backlight, also to the backlight in the actual dimmer switch, to the backlights for the reading lights, map light switch, and interior light switch, storage compartment light(not sure what that is) and cupholder backlight.

I have not decoded the wires which control the dimming in the a/c heat control unit itself since there are several wires coming from the J285 going to the A/C control unit (E87).

Mike