Coming up short....
05-30-2002, 10:05 PM
#1
User
Thread Starter
Coming up short....
Had to hop into Pattycakes and "beat feet" twice in the last week.
Serious storms - pitch dark at 6:00PM -, garage packed with windows for the house remodeling.
It was so dark that when I turned on the lights I could see the glow from my side marker lights.
When I touched the brakes my left side markers, and left running lights went out again - fuse - but I noticed when I hit the brakes again my right side markers really brightened -up... all of them, at the same time.
I have replaced all of the bulbs at the same time, cleaned every socket and connector.
All lights work until I touch the brakes.
So, before I string new wire from front to rear a few questions.
1. Could this be the result of the dreaded Passenger Power Brake Syndrom ?
2. The marker/running/brakelights should be on the same circuit and in the same cable run, correct?
What differentiates front and rear running light's other than a double filament bulb in the rear?
3. Has anyone had a similar problem or know where in the system the brake and marker lamp wiring would overlap and be crushed togther by "something"?
All short cuts investigated ... no matter how long it takes!
TIA,
John S. and Pattycakes, the recuperating Weissach.
( <img src="graemlins/beerchug.gif" border="0" alt="[cheers]" /> <img src="graemlins/crying.gif" border="0" alt="[crying]" /> <img src="graemlins/drink.gif" border="0" alt="[cherrsagai]" />
Serious storms - pitch dark at 6:00PM -, garage packed with windows for the house remodeling.
It was so dark that when I turned on the lights I could see the glow from my side marker lights.
When I touched the brakes my left side markers, and left running lights went out again - fuse - but I noticed when I hit the brakes again my right side markers really brightened -up... all of them, at the same time.
I have replaced all of the bulbs at the same time, cleaned every socket and connector.
All lights work until I touch the brakes.
So, before I string new wire from front to rear a few questions.
1. Could this be the result of the dreaded Passenger Power Brake Syndrom ?
2. The marker/running/brakelights should be on the same circuit and in the same cable run, correct?
What differentiates front and rear running light's other than a double filament bulb in the rear?
3. Has anyone had a similar problem or know where in the system the brake and marker lamp wiring would overlap and be crushed togther by "something"?
All short cuts investigated ... no matter how long it takes!
TIA,
John S. and Pattycakes, the recuperating Weissach.
( <img src="graemlins/beerchug.gif" border="0" alt="[cheers]" /> <img src="graemlins/crying.gif" border="0" alt="[crying]" /> <img src="graemlins/drink.gif" border="0" alt="[cherrsagai]" />
05-31-2002, 10:38 AM
#3
User
Thread Starter
Snow,
Thanks for the offer, even more thanks for the 'IDEA'!
The District Office got a peak at our time sheets and freaked so the entire highway renovation crew is off duty for a couple of days.
As a result I got up at O'Dark Early this morning and replaced the fuse and checked the bulbs , AGAIN...
Turned on the parking lights, hit the brakes and POOF the left side went out again.
Replaced the fuse, turned on the parking lights and idled for ten minutes...all lights O.K.,
turned on the headlights and fogs, idled for five minutes all O.K., touched the brakes and POOF!
New fuse - I got a million of them - turned parking lights on - all O.K., turned them off , hit brakes and, you got it, POOF. Here's the interesting part, with the left side marker fuse blown again, I hit the brakes again and the right side markers came on
WTF... I hit the brakes about ten times and the right side markers came on each time and stayed on until the brake was released. None of the right side bulbs burned out and the fuse didn't even get warm .
Pulled the fuse to the right side markers , put a new one in the left, checked the parking lights,
all O.K. . Hit the brakes and, Poof. Swapped all of the bulbs from right to left and left to right, new left fuse, hit the brakes, Poof , left side fuse blown again. <img src="graemlins/crying.gif" border="0" alt="[crying]" /> So, obviously, somrthing is amiss on the left side, If someone out there doesn't have a short cut I'll be stringing wire this week end.
If I do end up going this route ; Will it be necessary to string new wires to both sides due to resistance value differences in the new/old wire? I don't want to have an idiot light or the Bulb Management Switch getting confused.
TIA,
Where the hell's that Ohm meter got to now!
John S. and Clap on, Clap off, Pattycakes
<img src="graemlins/cussing.gif" border="0" alt="[grrrrrrr]" /> <img src="graemlins/drink.gif" border="0" alt="[cherrsagai]" />
Thanks for the offer, even more thanks for the 'IDEA'!
The District Office got a peak at our time sheets and freaked so the entire highway renovation crew is off duty for a couple of days.
As a result I got up at O'Dark Early this morning and replaced the fuse and checked the bulbs , AGAIN...
Turned on the parking lights, hit the brakes and POOF the left side went out again.
Replaced the fuse, turned on the parking lights and idled for ten minutes...all lights O.K.,
turned on the headlights and fogs, idled for five minutes all O.K., touched the brakes and POOF!
New fuse - I got a million of them - turned parking lights on - all O.K., turned them off , hit brakes and, you got it, POOF. Here's the interesting part, with the left side marker fuse blown again, I hit the brakes again and the right side markers came on
WTF... I hit the brakes about ten times and the right side markers came on each time and stayed on until the brake was released. None of the right side bulbs burned out and the fuse didn't even get warm .Pulled the fuse to the right side markers , put a new one in the left, checked the parking lights,
all O.K. . Hit the brakes and, Poof. Swapped all of the bulbs from right to left and left to right, new left fuse, hit the brakes, Poof , left side fuse blown again. <img src="graemlins/crying.gif" border="0" alt="[crying]" /> So, obviously, somrthing is amiss on the left side, If someone out there doesn't have a short cut I'll be stringing wire this week end.
If I do end up going this route ; Will it be necessary to string new wires to both sides due to resistance value differences in the new/old wire? I don't want to have an idiot light or the Bulb Management Switch getting confused.
TIA,
Where the hell's that Ohm meter got to now!
John S. and Clap on, Clap off, Pattycakes
<img src="graemlins/cussing.gif" border="0" alt="[grrrrrrr]" /> <img src="graemlins/drink.gif" border="0" alt="[cherrsagai]" />
05-31-2002, 01:06 PM
#4
Racer
John, please don't start rewiring Pancake just yet!
I looked over the wire diagrams late last night after reading your post and here is my .928 cents worth.
The only thing I can see that the brakes light circuit and side marker circuit have in common is the BCU. If you need a working copy of the wire diagram let me know.
1. Locate the Bulb Control Unit (BCU) and unplug it from the system.
2. With wire diagram in hand test each pin of the plug for shorts or continuity (don't forget to test the brake switch).
3. If no shorts are found and all pins show the correct readings, your problem will then point to the BCU, which Snow, has generously offered up.
If I’m in left field and have overlooked something on this, don’t hesitate to let me know, we all learn from our mistakes.
HTH
Max
I looked over the wire diagrams late last night after reading your post and here is my .928 cents worth.
The only thing I can see that the brakes light circuit and side marker circuit have in common is the BCU. If you need a working copy of the wire diagram let me know.
1. Locate the Bulb Control Unit (BCU) and unplug it from the system.
2. With wire diagram in hand test each pin of the plug for shorts or continuity (don't forget to test the brake switch).
3. If no shorts are found and all pins show the correct readings, your problem will then point to the BCU, which Snow, has generously offered up.
If I’m in left field and have overlooked something on this, don’t hesitate to let me know, we all learn from our mistakes.
HTH
Max
05-31-2002, 01:20 PM
#6
User
Thread Starter
Max, the schematics/diagram would be a fuge favor.
I don't want to splice on P'cakes unless I have to. If it goes that far I'll do a complete scale drawing and parts specification list for future ref. anf staple it in the Owners MAnual.
I wouldn't want to tap into Snow's parts stash - offer much appreciated - for I know the minute he puts it in the mail electrical gremlins would attack his WHITE.
I'll just order one if it's the culprit.
Thanks again.
John S.
<img src="graemlins/beerchug.gif" border="0" alt="[cheers]" /> 
I don't want to splice on P'cakes unless I have to. If it goes that far I'll do a complete scale drawing and parts specification list for future ref. anf staple it in the Owners MAnual.
I wouldn't want to tap into Snow's parts stash - offer much appreciated - for I know the minute he puts it in the mail electrical gremlins would attack his WHITE.
I'll just order one if it's the culprit.
Thanks again.
John S.
<img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />
05-31-2002, 01:25 PM
#7
User
Thread Starter
Max,
correction on the "fuge favor", been doing a lot of that lately>
HUGE FAVOR was the term.
or ... was that; por favor, senor....
John S. More <img src="graemlins/drink.gif" border="0" alt="[cherrsagai]" />
correction on the "fuge favor", been doing a lot of that lately>
HUGE FAVOR was the term.
or ... was that; por favor, senor....
John S. More <img src="graemlins/drink.gif" border="0" alt="[cherrsagai]" />
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05-31-2002, 02:10 PM
#8
Racer
Greg, Very good point! Here are a couple of ideas:
1. Remove BCU plug and all associated bulbs and check for a ground potential on the plus leads on the side marker circuit from the BCU plug side (should be lacking of a ground potential).
2. If no short is found (with BCU unplugged and all associated bulbs removed) install a jumper wire at BCU plug on the appropriate pin to a good ground and check for continuity at the bulb sockets and plug.
3. With BCU unplugged and all associated bulbs removed, install a fused (10 amp. max) 12VDC jumper wire at the BCU plug (at associated pin (s)) and test for your 12vdc at bulb sockets.
John, I will get it to you ASAP.
HTH
Max
1. Remove BCU plug and all associated bulbs and check for a ground potential on the plus leads on the side marker circuit from the BCU plug side (should be lacking of a ground potential).
2. If no short is found (with BCU unplugged and all associated bulbs removed) install a jumper wire at BCU plug on the appropriate pin to a good ground and check for continuity at the bulb sockets and plug.
3. With BCU unplugged and all associated bulbs removed, install a fused (10 amp. max) 12VDC jumper wire at the BCU plug (at associated pin (s)) and test for your 12vdc at bulb sockets.
John, I will get it to you ASAP.
HTH
Max
05-31-2002, 08:57 PM
#10
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Location: Land of many Potholes, Michigan
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John,
If you need a part, be small or big. Give me a shout. I don't mind helping other shark owners out. A few other owners know that now.
John D.
'85 928 Auto, Black
If you need a part, be small or big. Give me a shout. I don't mind helping other shark owners out. A few other owners know that now.
John D.
'85 928 Auto, Black
05-31-2002, 09:40 PM
#11
Racer
John, sent a few files earlier and am in the process of sending you a few more.
Let me know it you get them and if they are readable.
<img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />
Max
P.S. The files I am sending now will take several minutes to down load if you are on a dial-up connection.
Let me know it you get them and if they are readable.
<img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />
Max
P.S. The files I am sending now will take several minutes to down load if you are on a dial-up connection.
05-31-2002, 10:21 PM
#12
Three Wheelin'
Join Date: May 2001
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John,
The left front side markers and parking lights are of the same circuit, as well as the right front markers and parking lights.
Left markers, park lights same circuit.
Right markers, park lights same circuit
Both are fed from the light switch, left side through fuse #28/8A right side through fuse #29/8A. Left side wire connection is M5 on the fuse relay board Grey/brown wire.
Right side wire connection is M6 on the fuse relay board gray/red wire. The left side feed goes through a four-pole plug near the left front wheel well, wire color gray/brown into two blue wires.
Right side feed goes through a four-pole plug near the right front wheel well wire color gray/red into two blue wires. Check for a short there.
The rear left marker and rear taillight are on the same circuit fed from the lamp control unit, as well as the right marker and right rear taillight.
Left wire color gray/black then into a 4-pole connector in the spare wheel well out gray wires into the bulbs.
Right side wire colors gray/red into a 4-pole connector in the spare wheel well. Out gray wires to the bulbs.
The brake lights are on their own circuit. They all hang out at the lamp control unit, which houses a solid-state control. I suspect your problem lies within. It’s easier and cheaper just to change it. <img src="graemlins/drink.gif" border="0" alt="[cherrsagai]" />
<img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />
The left front side markers and parking lights are of the same circuit, as well as the right front markers and parking lights.
Left markers, park lights same circuit.
Right markers, park lights same circuit
Both are fed from the light switch, left side through fuse #28/8A right side through fuse #29/8A. Left side wire connection is M5 on the fuse relay board Grey/brown wire.
Right side wire connection is M6 on the fuse relay board gray/red wire. The left side feed goes through a four-pole plug near the left front wheel well, wire color gray/brown into two blue wires.
Right side feed goes through a four-pole plug near the right front wheel well wire color gray/red into two blue wires. Check for a short there.
The rear left marker and rear taillight are on the same circuit fed from the lamp control unit, as well as the right marker and right rear taillight.
Left wire color gray/black then into a 4-pole connector in the spare wheel well out gray wires into the bulbs.
Right side wire colors gray/red into a 4-pole connector in the spare wheel well. Out gray wires to the bulbs.
The brake lights are on their own circuit. They all hang out at the lamp control unit, which houses a solid-state control. I suspect your problem lies within. It’s easier and cheaper just to change it. <img src="graemlins/drink.gif" border="0" alt="[cherrsagai]" />
<img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />
05-31-2002, 10:42 PM
#13
User
Thread Starter
Max, I sent you back what came thru... Nada
Doz, Probably.
Steve, Really appreciate the walk thru.
All, thanks,
I need to get on the TT clamp ASAP and this has sped up my repair drudgery, considerably.
Then Laurie, my old neighbor and a hoot in her own right, comes rolling up in her new Kompressor.
Randy, when are you going to load the "slit my wrist", and "blow my brains out" Graemlins.
That is one nice Mercedes! And Laurie has that rub salt in the open wound just as sweet as can be Girl Gene- then of course my wife see's Laurie and the Kompressor leaving - they are good friends...I think? - Anyone see where this is leading... All I want to do is chase sparks. Honest Injun!!!
John S. <img src="graemlins/c.gif" border="0" alt="[ouch]" />
Doz, Probably.
Steve, Really appreciate the walk thru.
All, thanks,
I need to get on the TT clamp ASAP and this has sped up my repair drudgery, considerably.
Then Laurie, my old neighbor and a hoot in her own right, comes rolling up in her new Kompressor.
Randy, when are you going to load the "slit my wrist", and "blow my brains out" Graemlins.
That is one nice Mercedes! And Laurie has that rub salt in the open wound just as sweet as can be Girl Gene- then of course my wife see's Laurie and the Kompressor leaving - they are good friends...I think? - Anyone see where this is leading... All I want to do is chase sparks. Honest Injun!!!
John S. <img src="graemlins/c.gif" border="0" alt="[ouch]" />