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  #1  
Old 03-24-2011, 09:36 AM
rebreath's Avatar
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electrical gremlins present themselves.....

Greetings all.Been a while since I was here.have not had any major problems of late, until now that is....lol.I seem to be popping fuse 14 frequently for some reason.It controls the following:
1-back-up lamp....(working and does not cause poppage when put into reverse)
2-warning monitor term. 8..(dont know what this is, so unsure if it is the problem)
3-emission control..(egr?..if so, its disabled and has been for several years)
4-horn...(works and doesnt seem to cause fuse poppage when used)
5-switch-over valve overload protection device(not sure what/where this one is as well)
6-autom. trannsmission..(at the moment it wont "kick-down" when I press pedal to floor..this is with and without working fuse.)this one is a little tough to test in driveway at the moment.could this be the culprit?
7-relay aux fan.term. 86..(works when asked to work with no problems it seems)
8-control unit/water pump/heating water valve for climate control system...(if this is the little aux pump on passenger side near front of engine, it has a 1 amp fuse in place for CCU protection.fuse not blown.If its the mono-valve, then I am not sure how to test it.)

Car starts cold in the morning with no problems.this all started yesterday late in the day.Was not aware of it until I tried to blow horn to let someone in and got no sound at all.when fuse is replaced in garage,I can blow horn,put in reverse,turn CCU on and off with no problems.Seems to happen as soon as car begins moving.and not right at start, seems to happen after car is moving.
While in reality a blown fuse is not a major fix, but when it happens every time I drive, this gets old VERY quickly.Any and all suggestions and inputs will be greatly appreciated.

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  #2  
Old 03-24-2011, 10:26 AM
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heh, you could put in a bar of solid copper, and wait until the problem melts or burns your car to the ground...
not a good choice of course, I'd look at the kick down switch, pull up the carpet and unplug the switch. go for a drive and see if it pops the fuse still.
OVP should have it's own fuse... not sure on that one. but the relay would be in the passanger's kick panel if your car has one (thought it was only the 85's...)
CCU could be melted an you not know it... open up the panel, and unplug the CCU connectors. see if the problem goes away...
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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
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  #3  
Old 03-24-2011, 10:30 AM
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#2 & #5 could be possible culprits.
#2 Warning Module is underdash and gives your warning lights for battery voltage (alt.), brake, etc... Does all of your warning lights test after replacement?

#5 Overload Relief Sw. is connected to the intake manifold pressure switch for overboost protection. What may have happened is a pinched wire from a recent valve adjustment or other maintenance in the engine area. It's not hard to pinch a wire when reinstalling the valve cover.

Have you done any maintenance that might coincide with when this started occuring?
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Old 03-24-2011, 10:37 AM
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Quote:
Originally Posted by vstech View Post
heh, you could put in a bar of solid copper, and wait until the problem melts or burns your car to the ground...
not a good choice of course, I'd look at the kick down switch, pull up the carpet and unplug the switch. go for a drive and see if it pops the fuse still.
OVP should have it's own fuse... not sure on that one. but the relay would be in the passanger's kick panel if your car has one (thought it was only the 85's...)
CCU could be melted an you not know it... open up the panel, and unplug the CCU connectors. see if the problem goes away...
I will try this today if time(and discomfort) allows after dentist appt today.sound like it should be an easy check.
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Old 03-24-2011, 10:39 AM
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Quote:
Originally Posted by SD Blue View Post
#2 & #5 could be possible culprits.
#2 Warning Module is underdash and gives your warning lights for battery voltage (alt.), brake, etc... Does all of your warning lights test after replacement?

#5 Overload Relief Sw. is connected to the intake manifold pressure switch for overboost protection. What may have happened is a pinched wire from a recent valve adjustment or other maintenance in the engine area. It's not hard to pinch a wire when reinstalling the valve cover.

Have you done any maintenance that might coincide with when this started occuring?
I just recently had the aircan off to repair the mount AGAIN(used a screw and red locktite this time....lol), could it pinch that same wire?

I will check the dummy lites and see if there is a change.

I checked the kickdown switch under pedal and it definitely popped the fuse.Does this mean the switch is bad or the device it controls?Also , if its the switch..how does the #$*@! thing come out?

Sam
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Last edited by vstech; 03-24-2011 at 11:17 AM.
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  #6  
Old 03-24-2011, 11:19 AM
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the switch should just be clipped into the bracket under the pedal.
should pull right out.
you may need to remove the clip from the bottom of the pedal first to get room to work.
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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!
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  #7  
Old 03-24-2011, 08:55 PM
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Check for a loose wire or broken clip on the tranny. Maybe not the switch but the wire.

It 'might' also be the wire in the console for the gear selector. In/out of reverse okay, but what happens going through all the gears? That wire is on the same branch as the kickdown, but if you've tried the kickdown and it trips the fuse that's probably it.
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Old 03-25-2011, 09:26 AM
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Quote:
Originally Posted by Yak View Post
Check for a loose wire or broken clip on the tranny. Maybe not the switch but the wire.

It 'might' also be the wire in the console for the gear selector. In/out of reverse okay, but what happens going through all the gears? That wire is on the same branch as the kickdown, but if you've tried the kickdown and it trips the fuse that's probably it.
got the switch out and did a resistance test on it and got a reading of .4 with switch closed and zero of course with it open.Not sure what the values should test to when closed though.For the moment (starting yesterday) I have been using the gear selector to shift manually when needed.I go up and down a large hill dily and that end seems to working okay.Where on the tranny does the wire(s) go?Is there a way to test the solenoid that it operates? and lastly but most importantly how difficult of a repair is this potentially?
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Old 03-25-2011, 03:08 PM
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Quote:
Originally Posted by rebreath View Post
got the switch out and did a resistance test on it and got a reading of .4 with switch closed and zero of course with it open.Not sure what the values should test to when closed though.For the moment (starting yesterday) I have been using the gear selector to shift manually when needed.I go up and down a large hill dily and that end seems to working okay.Where on the tranny does the wire(s) go?Is there a way to test the solenoid that it operates? and lastly but most importantly how difficult of a repair is this potentially?
The kickdown solenoid is on the passenger side rear of the tranny. If the wire is chafed or loose it could short to ground whenever the switch is closed. There might be a zip-tie holding it.

I don't have info or a good switch to compare to regarding measurements but I think the switch itself when disconnected should probably be infinite ohms when open (sitting there) and zero ohms when closed (depressed). 0.4 may simply be a poor/dirty probe connection.

Do you go full-throttle a lot? My understanding is that's how the kickdown is supposed to be adjusted. There's a depth adjustment with the threaded collar.
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Old 03-25-2011, 04:31 PM
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Quote:
Originally Posted by Yak View Post
The kickdown solenoid is on the passenger side rear of the tranny. If the wire is chafed or loose it could short to ground whenever the switch is closed. There might be a zip-tie holding it.

I don't have info or a good switch to compare to regarding measurements but I think the switch itself when disconnected should probably be infinite ohms when open (sitting there) and zero ohms when closed (depressed). 0.4 may simply be a poor/dirty probe connection.

Do you go full-throttle a lot? My understanding is that's how the kickdown is supposed to be adjusted. There's a depth adjustment with the threaded collar.
Excellent ...thanks for the placement info.I dont usually go full throttle to much(only for tailgaters, gotta love the back-off smoke...lol).But living in western Pa., i do have to kick her down frequently for hills.I will check the adjustment after I find the solenoid.If I need to replace the solenoid, is used generally acceptable?Or is this a preferred new part?

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