Headlight Motor Direction Problem
09-03-2013, 08:34 AM
#16
Rennlist Member
Thread Starter
Maybe Alan will chime in here,
from the what your reporting,
there may be a diode thats burned out in the motor thus letting it continue to run,
Alan was addressing this issue for someone else a few days ago in the mean time dont let the arm hit the condenser it will hole it
from the what your reporting,
there may be a diode thats burned out in the motor thus letting it continue to run,
Alan was addressing this issue for someone else a few days ago in the mean time dont let the arm hit the condenser it will hole it
09-03-2013, 08:36 AM
#17
Rennlist Member
Thread Starter
The motor shouldn't be looking for a hard stop. Its internal position sensors should sense the traverse 180 deg to the other up or down position and then stop of its own accord. Then signal sent to relay regarding its achieved position. That's why they go up, stop, and then the light illuminates. I don't know if a Euro is different.
Jeff, if you set it as described it should work. If not internal motor issue. Detach the large cylindrical harness above the motor and raise/lower by hand. Illumination will still work from the switch. I had to do this for a spell when I had a similar issue.
Jeff, if you set it as described it should work. If not internal motor issue. Detach the large cylindrical harness above the motor and raise/lower by hand. Illumination will still work from the switch. I had to do this for a spell when I had a similar issue.
09-03-2013, 10:22 AM
#18
Rennlist Member
I would suggest changing out the relay first, however it could be a diode in the motor. I had an issue w/ my headlights on my 85, which has the non reversing earlier version, I think 87 up they started reversing when the ac/condensers got wider.
After taking the motor apart, I discovered it was in fact the new relay that I had replaced only a year ago! At least the motor got a good cleaning and lube
Dave
After taking the motor apart, I discovered it was in fact the new relay that I had replaced only a year ago! At least the motor got a good cleaning and lube
Dave
09-03-2013, 11:14 AM
#19
Rennlist Member
As I can understand, the whole process is switched by the contact strips on the idler wheel inside the motor assembly [I think there are two- one for up one for down].
When rotation reaches a certain position the contact sensor runs out of exposed conducting surface and the electrical current to the motor is stopped by the relay. This presumably tells the main relay where the system is in its cycle and thus thinks the headlights are fully upright therefore switching current onto the bulbs. When you switch the lights off, the relay cuts off the power supply to the lights, and puts a reverse polarity voltage on the motor which causes it to rotate the other way. When the contact patch on the corresponding contact strip runs out of contact patch, the motor stops.
You can test this concept quite easily by disconnecting the connecting [actuation] rod on the motor assembly, the lights will be retracted, and when you switch on the lights [get a friend to do this] you should see the output shaft rotate something over half a rotation and then the lights, in the retracted position wil illuminate. Similar when you switch off the lights, the thing goes out and the motor should retrun to the reverse position.
Assuming this all works correctly I then drive the idler shaft to the full on position, pull th elights up by hand and with someone holding them in position- connect the conrod to the splined shaft.
For the drive shaft to over rotate, it would require current to be retained when the pick up is past the exposed metal contact surface - does not seem likely. Thus, if the exposed strip is what triggers the relay to stop the motor, the only explanation for over rotation would be a relay failure on the appropriate contact I suspect. I experienced something like this with my "failed" relay.
Doubtless Alan can explain this technically better than I can.
It is very easy to open up the motor and clean the contact points but I doubt those are problemmatical.
Regards
Fred
When rotation reaches a certain position the contact sensor runs out of exposed conducting surface and the electrical current to the motor is stopped by the relay. This presumably tells the main relay where the system is in its cycle and thus thinks the headlights are fully upright therefore switching current onto the bulbs. When you switch the lights off, the relay cuts off the power supply to the lights, and puts a reverse polarity voltage on the motor which causes it to rotate the other way. When the contact patch on the corresponding contact strip runs out of contact patch, the motor stops.
You can test this concept quite easily by disconnecting the connecting [actuation] rod on the motor assembly, the lights will be retracted, and when you switch on the lights [get a friend to do this] you should see the output shaft rotate something over half a rotation and then the lights, in the retracted position wil illuminate. Similar when you switch off the lights, the thing goes out and the motor should retrun to the reverse position.
Assuming this all works correctly I then drive the idler shaft to the full on position, pull th elights up by hand and with someone holding them in position- connect the conrod to the splined shaft.
For the drive shaft to over rotate, it would require current to be retained when the pick up is past the exposed metal contact surface - does not seem likely. Thus, if the exposed strip is what triggers the relay to stop the motor, the only explanation for over rotation would be a relay failure on the appropriate contact I suspect. I experienced something like this with my "failed" relay.
Doubtless Alan can explain this technically better than I can.
It is very easy to open up the motor and clean the contact points but I doubt those are problemmatical.
Regards
Fred
09-03-2013, 12:01 PM
#20
Rennlist Member
Thread Starter
As I can understand, the whole process is switched by the contact strips on the idler wheel inside the motor assembly [I think there are two- one for up one for down].
When rotation reaches a certain position the contact sensor runs out of exposed conducting surface and the electrical current to the motor is stopped by the relay. This presumably tells the main relay where the system is in its cycle and thus thinks the headlights are fully upright therefore switching current onto the bulbs. When you switch the lights off, the relay cuts off the power supply to the lights, and puts a reverse polarity voltage on the motor which causes it to rotate the other way. When the contact patch on the corresponding contact strip runs out of contact patch, the motor stops.
You can test this concept quite easily by disconnecting the connecting [actuation] rod on the motor assembly, the lights will be retracted, and when you switch on the lights [get a friend to do this] you should see the output shaft rotate something over half a rotation and then the lights, in the retracted position wil illuminate. Similar when you switch off the lights, the thing goes out and the motor should retrun to the reverse position.
Assuming this all works correctly I then drive the idler shaft to the full on position, pull th elights up by hand and with someone holding them in position- connect the conrod to the splined shaft.
For the drive shaft to over rotate, it would require current to be retained when the pick up is past the exposed metal contact surface - does not seem likely. Thus, if the exposed strip is what triggers the relay to stop the motor, the only explanation for over rotation would be a relay failure on the appropriate contact I suspect. I experienced something like this with my "failed" relay.
Doubtless Alan can explain this technically better than I can.
It is very easy to open up the motor and clean the contact points but I doubt those are problemmatical.
Regards
Fred
When rotation reaches a certain position the contact sensor runs out of exposed conducting surface and the electrical current to the motor is stopped by the relay. This presumably tells the main relay where the system is in its cycle and thus thinks the headlights are fully upright therefore switching current onto the bulbs. When you switch the lights off, the relay cuts off the power supply to the lights, and puts a reverse polarity voltage on the motor which causes it to rotate the other way. When the contact patch on the corresponding contact strip runs out of contact patch, the motor stops.
You can test this concept quite easily by disconnecting the connecting [actuation] rod on the motor assembly, the lights will be retracted, and when you switch on the lights [get a friend to do this] you should see the output shaft rotate something over half a rotation and then the lights, in the retracted position wil illuminate. Similar when you switch off the lights, the thing goes out and the motor should retrun to the reverse position.
Assuming this all works correctly I then drive the idler shaft to the full on position, pull th elights up by hand and with someone holding them in position- connect the conrod to the splined shaft.
For the drive shaft to over rotate, it would require current to be retained when the pick up is past the exposed metal contact surface - does not seem likely. Thus, if the exposed strip is what triggers the relay to stop the motor, the only explanation for over rotation would be a relay failure on the appropriate contact I suspect. I experienced something like this with my "failed" relay.
Doubtless Alan can explain this technically better than I can.
It is very easy to open up the motor and clean the contact points but I doubt those are problemmatical.
Regards
Fred
So it sounds like pulling the relay and cleaning it or looking for a failed component in it would be the best first step. Can I get some advice on how to pull this relay without destroying it?
Also as I have no knowledge of what to look for inside should it be obvious that something is wrong or does someone have a testing procedure that I can use on my workbench to see what the relay will do.
If I am told what pins to apply voltage to and where and what to expect for output I can do that easy. I can get a cheapo 12v battery at walmart and begin testing the relay.
don't want to drive the arm into the condenser anymore!
09-03-2013, 12:23 PM
#21
Nordschleife Master
09-03-2013, 12:41 PM
#22
Rennlist Member
So it sounds like pulling the relay and cleaning it or looking for a failed component in it would be the best first step. Can I get some advice on how to pull this relay without destroying it?
Also as I have no knowledge of what to look for inside should it be obvious that something is wrong or does someone have a testing procedure that I can use on my workbench to see what the relay will do.
If I am told what pins to apply voltage to and where and what to expect for output I can do that easy. I can get a cheapo 12v battery at walmart and begin testing the relay.
don't want to drive the arm into the condenser anymore!
Also as I have no knowledge of what to look for inside should it be obvious that something is wrong or does someone have a testing procedure that I can use on my workbench to see what the relay will do.
If I am told what pins to apply voltage to and where and what to expect for output I can do that easy. I can get a cheapo 12v battery at walmart and begin testing the relay.
don't want to drive the arm into the condenser anymore!
I would disconnect the battery, pull the LH/EZ assembly to give yourself some room. I then removed either one or two relays adjacent [LHS] to the light unit relay. Soemtimes pulling these things is a royal pain the *** but they usually come out after a bit of rocking and brute force. generally, if you do pull the top cover off, they are usually quite simple to reposition. If you have space, you can usually use a small screw driver to lever under the relay base hence better to disconnect the battery if you do this.
I found the lights relay came out quite easily as there is a lot to grab hold of- I rocked it backwards and forwards and applied some outwards pull simultaneously. I then had no problems getting it in and out.
If you carried out the test I mentioned, as long as the lights switch on and off you can simply disconnect the power supply to the actuator and use the manual **** to raise/lower as/when needed. I did that for a couple of weeks until I worked out what the inital problem was .
I still have to resolve the issues I reported the other day but at least I have some clues as to where to start looking fine adjustment wise.
Best solution is if you can get hold of a known good relay from a S4 owning friend and try it- at least that gives you some direction.
Regards
Fred
09-03-2013, 12:57 PM
#23
Electron Wrangler
Lifetime Rennlist
Member
Lifetime Rennlist
Member
There is a wiper track in the motor that controls the location of the up stop point and the down stop point. These feed the relay that interprets these to control the motor. If either of these malfunctions you can have over rotation.
I'd disassemble the motor & R&R or at least monitor the swicth outputs during manual rotation to test use an ohmmeter between Pins 2, 3 & 4 on the HL motor connector 4 is the common.
Seems you tried another Relay already? Note that Pre-S4 relays are not compatible with the later cars.
See where you see the continuity breaks Vs. physical positions.
Alan
I'd disassemble the motor & R&R or at least monitor the swicth outputs during manual rotation to test use an ohmmeter between Pins 2, 3 & 4 on the HL motor connector 4 is the common.
Seems you tried another Relay already? Note that Pre-S4 relays are not compatible with the later cars.
See where you see the continuity breaks Vs. physical positions.
Alan
09-03-2013, 01:47 PM
#24
Rennlist Member
Thread Starter
There is a wiper track in the motor that controls the location of the up stop point and the down stop point. These feed the relay that interprets these to control the motor. If either of these malfunctions you can have over rotation.
I'd disassemble the motor & R&R or at least monitor the swicth outputs during manual rotation to test use an ohmmeter between Pins 2, 3 & 4 on the HL motor connector 4 is the common.
Seems you tried another Relay already? Note that Pre-S4 relays are not compatible with the later cars.
See where you see the continuity breaks Vs. physical positions.
Alan
I'd disassemble the motor & R&R or at least monitor the swicth outputs during manual rotation to test use an ohmmeter between Pins 2, 3 & 4 on the HL motor connector 4 is the common.
Seems you tried another Relay already? Note that Pre-S4 relays are not compatible with the later cars.
See where you see the continuity breaks Vs. physical positions.
Alan
So, to ever expose my lack of understanding of electrics, I'll repeat what I think you wrote.
I should disconnect the power plug above the manual **** to the motor. Then check continuity between pins 2&4 and 3&4 with my ohm meter? This should give me an understanding of where the power is being applied or not being applied throughout the cycle of the motor?
I will see if I can do this over lunchtime and report back. At least I can hook up the arm again and get manual lights.
Then we can determine if it is the motor or the relay correct?
09-03-2013, 02:06 PM
#26
Electron Wrangler
Lifetime Rennlist
Member
Lifetime Rennlist
Member
Maybe Alan will chime in here,
from the what your reporting,
there may be a diode thats burned out in the motor thus letting it continue to run,
Alan was addressing this issue for someone else a few days ago in the mean time dont let the arm hit the condenser it will hole it
from the what your reporting,
there may be a diode thats burned out in the motor thus letting it continue to run,
Alan was addressing this issue for someone else a few days ago in the mean time dont let the arm hit the condenser it will hole it
Alan
09-03-2013, 02:15 PM
#27
Electron Wrangler
Lifetime Rennlist
Member
Lifetime Rennlist
Member
I dont follow how the arm can hit the condenser with all the clips in place ??? Does the motor actually change direction between up and down?
I had an issue early in my ownership, which I had to fix with a new relay, having checked inside the motor case and the 4 wire connector.
jp 83 Euro S AT 55k
I had an issue early in my ownership, which I had to fix with a new relay, having checked inside the motor case and the 4 wire connector.
jp 83 Euro S AT 55k
So the shaft drive mechanism on an S4 (+) is designed for only one half cycle operation - the other half should never happen...
Alan
09-03-2013, 02:20 PM
#28
Nordschleife Master
I looked at the linkage and can see how it transcribes an arc. I set it at what appears to be the bottom of the arc and tried it. When I assmebled it, it went to the top and past a bit. Then when I turned off the lights, it tried to continue around and hit the condenser again. With the arm off my motor when you turn it on, the splined shaft goes round and round and round and the headlights blink on/off on/off until you turn the light switch off. When you turn it off, it goes to a certain point and stops. Is this normal or is there a limit switch in the headlight travel path that says "whoa!" and the motor stops there and reverses direction when switch is turned off?
Do you put the arm on at the up position or the bottom position? I pulled the entire linkage apart and have all the clips and washers and arms on my bench. I have tried both ways but am missing something. Don't want to hit the condenser too many more times or I'll end up needing a new one. Doesn't leak yet but has some nice gouges.
Do you put the arm on at the up position or the bottom position? I pulled the entire linkage apart and have all the clips and washers and arms on my bench. I have tried both ways but am missing something. Don't want to hit the condenser too many more times or I'll end up needing a new one. Doesn't leak yet but has some nice gouges.
This changes the thought directly to internal motor malfunction.
09-03-2013, 03:15 PM
#29
Rennlist Member
Thread Starter
I tested the continuity between pins 2&4 and pins 3&4 with my multimeter. Here is what I did.
I turned the lights on then off with the key on so i could get the motor to cycle to the known good stop point in the headlights down position.
I then turned the key off and unplugged the motor plug behind the manual ****.
I connected my multimeter to pins 2&4 and manually raised the headlights to the full up position.
I got 0 ohms at the starting point. As I rotated up, the ohms began to climb to .1 and then moved up through the raising of the lights to cumulate around 5 or so on my meter at the top position, they then fell off to zero at about 5 degrees over rotated. Ohms varied by the speed of me turning the ****.
After I got to the top I then connected my multimeter to pins 3&4.
I started at the full up position and over rotated the lights backwards. I saw 0 ohms as I went past the full up and was going backwards.
I lowered the lights and saw between .1 and 3 ohms through the arc to the parked position of the lights. then I saw 0 ohms in the parked position.
What this means is?????
Should I pull the motor anyway and clean the wipers off (if I can figure out to to remove the motor and take it apart.)? Looks like you remove the three m6 or m4 bolts on the side by the splined shaft and lift it straight out?
Then I would guess the motor casing comes off and I can clean the "wipers" that reside inside the motor? Any photos of the process of removal and taking the motor apart? I can't find anything about this in the WSMs.
or
Should I suspect the relay and pull that? If so, how do I test the relay?
I turned the lights on then off with the key on so i could get the motor to cycle to the known good stop point in the headlights down position.
I then turned the key off and unplugged the motor plug behind the manual ****.
I connected my multimeter to pins 2&4 and manually raised the headlights to the full up position.
I got 0 ohms at the starting point. As I rotated up, the ohms began to climb to .1 and then moved up through the raising of the lights to cumulate around 5 or so on my meter at the top position, they then fell off to zero at about 5 degrees over rotated. Ohms varied by the speed of me turning the ****.
After I got to the top I then connected my multimeter to pins 3&4.
I started at the full up position and over rotated the lights backwards. I saw 0 ohms as I went past the full up and was going backwards.
I lowered the lights and saw between .1 and 3 ohms through the arc to the parked position of the lights. then I saw 0 ohms in the parked position.
What this means is?????
Should I pull the motor anyway and clean the wipers off (if I can figure out to to remove the motor and take it apart.)? Looks like you remove the three m6 or m4 bolts on the side by the splined shaft and lift it straight out?
Then I would guess the motor casing comes off and I can clean the "wipers" that reside inside the motor? Any photos of the process of removal and taking the motor apart? I can't find anything about this in the WSMs.
or
Should I suspect the relay and pull that? If so, how do I test the relay?
Last edited by jeff spahn; 09-03-2013 at 03:17 PM. Reason: add more stuff
09-03-2013, 03:51 PM
#30
Electron Wrangler
Lifetime Rennlist
Member
Lifetime Rennlist
Member
Depending on what you mean exactly - Seems the motor & track probably works fine - a few ohms is no problem.
BUT When you say 0 ohms at parked position - I assume you mean open circuit (which is actually ~infinite ohms) please clarify?
Seems (based on a presumption here) its probably the relay... DVM's often represent OC in non-intuitive ways...
Alan
BUT When you say 0 ohms at parked position - I assume you mean open circuit (which is actually ~infinite ohms) please clarify?
Seems (based on a presumption here) its probably the relay... DVM's often represent OC in non-intuitive ways...
Alan