Go Back   FerrariChat.com > Model Specific Discussions > 308/328 - Sponsored by Yellow Compass Group

Reply
 
LinkBack Thread Tools
  #1  
Old 07-16-2017, 06:29 PM
Karting
Not Subscribed
 
Join Date: Sep 2013
Location: Jacksonville,Florida
Full Name: "VD"
Posts: 100
Headlight headaches

My normally very reliable and mild-mannered 85 QV is mad at me. I was out of town for a few months, and in my absence, her headlights started malfunctioning. First, they wouldn't turn on, (but went up) and then, they starting cycling up and down continuously. I've been a little busy since all this trouble started, so I only got to working on it today. Over a beer or two, my friend and I went through a number of trouble-shooting steps, as described below, with no luck, and have come to the rather baffling conclusion that both motors have a bad diode. I am never comfortable with the idea of simultaneous bilateral failures without an apparent common cause, so I will describe our methods and findings, in case any of you brilliant 308ers might have some insight onto what else I can try.

Initial malfunction state: as of this morning, rotating the light switch to the ON position, (with stalk in center position) initiates an endless cycling of the headlight buckets (they go up and down, one slightly faster than the other, gradually getting off-phase). When the light switch is rotated to the OFF position, the lights turn off, and the headlights freeze in their current position (IE: they DO NOT self-park, as they should). Light motor cycling occurs identically in the other two stalk positions correlating to high-beams and parking lights. Lights do not illuminate in any switch or stalk position.

First corrective action: removed light switch cap from stalk. Noted broken sodder connection on green wire. Fixed sodder connection, and reassembled switch.

Result: Same exact behavior (cycling motors, no self-park) except that the lights now work (correctly in all three stalk-positions).

Second action: removed and replaced 30 AMP headlight motor-control relay with (presumed) good spare.

Result: No change in malfunction.

Third action: Removed and replaced each individual 20/30 AMP motor relay with a known good relay from elsewhere on the panel.

Result: No change in malfunction.

Forth action: opened and checked resistance on the two connections to each headlight motor. Each motor has two pairs of wires. A black and black/gray pair, and a green, green/black pair. As we understand it, each pair goes to one of two diodes in the headlamp motor. We would expect detectable one way flow through each pair. So low resistance, measured in one direction across a wire-pair, and infinite resistance in the other direction across the same pair.

Result: tested both motors, reading resistance each way across both pairs. We got the expected results (infinite, and 0.5) on the black and black/gray pairs on BOTH headlight motors, and we got the infinite in BOTH directions on BOTH of the green and green-black pair. In other words, we did not find a smoking gun. we found TWO smoking guns--which made us question our understanding of the system. All we know know is that they are either BOTH good, or they BOTH have one bad diode connecting the green and green/black wires.

Fifth Action: just for GP, we left one headlight motor disconnected, and turned on the headlight switch, then reversed the configuration to test other side in isolation.

Result: powered in isolation, each headlight exhibited the same behavior as previously, cycling up and down, and not self-parking when the switch was turned off.

At that point, we were out of ideas that did not involve removing the headlight motors, cutting through the thick rubbery crud they are coated in, and trying to replace one or both diodes. That seemed like entirely too much work to start at 4:30 in the afternoon on a Sunday, when we had been messing around with various old cars since 9:30 in the morning.

The one thing I thought of, but did not check was the steering column connection of the light switch stalk; but since the lights themselves illuminate correctly, (now that I soddered the wire in the switch back in) I kind of doubt that has anything to do with it.

The only thing I can figure is that (maybe) having a broken/intermittent connection in the switch might have somehow damaged the control diodes in both motors. Seems far-fetched, but that is the only way I can believe the results I am seeing.

That, or my car is just trying to punish me for my protracted absence.

Any suggestions? Thoughts? Pearls of wisdom?

Thanks in advance for the help.
Reply With Quote
Non-Sponsor Ads
  #2  
Old 07-17-2017, 08:33 AM
thorn's Avatar
Karting
Silver Subscribed
 
Join Date: Aug 2012
Location: Tallahassee, FL
Posts: 126
I had exactly this problem with my first car - a 1984 Corolla GTS. Every time the pods activated, they did a dance.

At first, they'd both go up/down together and finally settle into the correct position. Later, they'd both dance, but get out of sequence. Finally, they got to the point that they were both randomly dancing to a different beat, and then would just stop in some random position (rendering the headlights useless). It was maddening.

The dealer found the fix; as I recall (it's been 30 years) they replaced two 1-2" electrical boxes; I know at least one was a relay.

So my gut tells me it's probably not your diodes; you're right - it's weird that they would BOTH go bad at the same time. If they have, then you've got (or had) another problem up the line that killed them both in the same moment.

I also don't think it's your switch, btw.

Another test to try: take off the cabin/electric cover panel. When they're dancing, are you hearing the relays click repeatedly? Or clicks with odd delays, or wrong # of clicks? Or is it just the initial "activation relay click", and then they dance regardless? If the relays keeping clicking, there's a problem area.

If it's just once, then we know that switch+relay = proper signal to pods, therefore behavior = problem down the chain. If it's multiple clicks, then we can guess that signal = telling pods to go on/off repeatedly.

Last edited by thorn; 07-17-2017 at 08:43 AM.
Reply With Quote
  #3  
Old 07-17-2017, 01:05 PM
Karting
Not Subscribed
 
Join Date: Sep 2013
Location: Jacksonville,Florida
Full Name: "VD"
Posts: 100
Quote:
Originally Posted by thorn View Post
I

So my gut tells me it's probably not your diodes; you're right - it's weird that they would BOTH go bad at the same time. If they have, then you've got (or had) another problem up the line that killed them both in the same moment.

I also don't think it's your switch, btw.

Another test to try: take off the cabin/electric cover panel. When they're dancing, are you hearing the relays click repeatedly? Or clicks with odd delays, or wrong # of clicks? Or is it just the initial "activation relay click", and then they dance regardless? If the relays keeping clicking, there's a problem area.

If it's just once, then we know that switch+relay = proper signal to pods, therefore behavior = problem down the chain. If it's multiple clicks, then we can guess that signal = telling pods to go on/off repeatedly.
From my recollection (I'm nowhere near her right now, so I can't test my memory) I am getting multiple clicks from the relay board. I thought we had conclusively eliminated the possibility of a bad relay by swapping several out, but I wasn't able to swap BOTH light relays at the same time, because I only had one known-good spare. Short of breaking open two potentially four-oh motors, that is probably worth looking at again.

Thanks.
Reply With Quote
  #4  
Old 07-17-2017, 01:54 PM
Formula Junior
Not Subscribed
 
Join Date: Mar 2012
Location: UK
Posts: 337
It's not just a bad relay that you need to watch for, you might have a bad connection on the relay board. Use some contact cleaner, Servisol or similar, and spray it in all the contacts before you refit the relay. Also check the connectors on the back of the relay board.
Reply With Quote
  #5  
Old 07-17-2017, 02:42 PM
miketuason's Avatar
F1 World Champ
Rossa Subscribed
 
Join Date: Feb 2006
Location: Cerritos, CA.
Full Name: Mike
Posts: 11,690
My Garage
This could be your culprit, one of the wire or both wire sometime comes unsolder in side the rotating knob. I had the same problem befor, resoldered the wire and all is good now.
Attached Images
File Type: jpg IMG_0443.JPG (29.9 KB, 135 views)
__________________
Ferrari and McIntosh, After a long drive in a Ferrari, sitting in front of a McIntosh audiophile system relaxes me.
Reply With Quote
  #6  
Old 07-17-2017, 02:58 PM
Karting
Not Subscribed
 
Join Date: Mar 2010
Location: Hill Island
Full Name: Paul XXXcX
Posts: 189
he wrote he re soldered...
over time things corrode...without checking the wire diagram...is there a ground connection to the motors that may have gone bad? For testing you can just run a fresh ground wire from battery/chassis to the point on the pods. The other is actually connectors, so if there is a male/female connector along the way, unplug, check maybe scrape/use deoxit type cleaners. The board of course is also a possible source. Good luck!
Reply With Quote
  #7  
Old 07-17-2017, 03:10 PM
ME308's Avatar
Formula 3
Silver Subscribed
 
Join Date: Nov 2003
Location: Munich, Germany
Full Name: Michael
Posts: 1,330
Quote:
Originally Posted by Patrick Dixon View Post
It's not just a bad relay that you need to watch for, you might have a bad connection on the relay board. ...
this !

press (very) hard on the relais - one at a time - while the headlight motors are dancing

see what happens
Reply With Quote
  #8  
Old 07-17-2017, 06:29 PM
Karting
Not Subscribed
 
Join Date: Sep 2013
Location: Jacksonville,Florida
Full Name: "VD"
Posts: 100
Quote:
Originally Posted by miketuason View Post
This could be your culprit, one of the wire or both wire sometime comes unsolder in side the rotating knob. I had the same problem befor, resoldered the wire and all is good now.
Believe me, I was very excited when I first took off the stalk end cap and saw that broken solder on the green wire. I was commensurately annoyed to find out that doing so did not solve my problem.
Reply With Quote
Non-Sponsor Ads
  #9  
Old 07-17-2017, 06:32 PM
Karting
Not Subscribed
 
Join Date: Sep 2013
Location: Jacksonville,Florida
Full Name: "VD"
Posts: 100
Quote:
Originally Posted by braq View Post
he wrote he re soldered...
over time things corrode...without checking the wire diagram...is there a ground connection to the motors that may have gone bad? For testing you can just run a fresh ground wire from battery/chassis to the point on the pods. The other is actually connectors, so if there is a male/female connector along the way, unplug, check maybe scrape/use deoxit type cleaners. The board of course is also a possible source. Good luck!
I would think that a bad ground would stop the motor from working entirely--not send them dancing up and down. But yeah, I suppose I should eliminate that. Thanks.
Reply With Quote
  #10  
Old 07-17-2017, 06:37 PM
Karting
Not Subscribed
 
Join Date: Sep 2013
Location: Jacksonville,Florida
Full Name: "VD"
Posts: 100
Quote:
Originally Posted by Patrick Dixon View Post
It's not just a bad relay that you need to watch for, you might have a bad connection on the relay board. Use some contact cleaner, Servisol or similar, and spray it in all the contacts before you refit the relay. Also check the connectors on the back of the relay board.
I DID check the back of the board to see if any of the wires were out, but I can't say it was an exhaustive look. We did not check for corrosion and individual circuit integrity. That probably merits closer examination. Good point.
Reply With Quote
  #11  
Old 07-18-2017, 04:09 PM
Archer911's Avatar
Formula Junior
Silver Subscribed
 
Join Date: Sep 2016
Location: New England
Full Name: Tim
Posts: 493
I am also having this problem intermittently.
Reply With Quote
  #12  
Old 07-18-2017, 09:34 PM
Karting
Not Subscribed
 
Join Date: Sep 2013
Location: Jacksonville,Florida
Full Name: "VD"
Posts: 100
Quote:
Originally Posted by Archer911 View Post
I am also having this problem intermittently.
I'll let you know when I solve it!

Today, I bought a few replacement relays, and swapped out all three of the headlight motor-related ones simultaneously. No change. Now I have some extra relays though...

I have a plan to test the headlights motors on my friend's 308 using the same protocol I used on my car. If I get the same results, I can say with reasonable certainty that the fault lays elsewhere. If the result differs, I will tear open my motors and swap out the diodes.
Reply With Quote
  #13  
Old Yesterday, 08:44 AM
Saabguy's Avatar
Formula Junior
Silver Subscribed
 
Join Date: Mar 2012
Location: Shreveport, LA
Posts: 956
A bad ground could give you a ground loop where the current flows backward through something. Like putting in the wrong type of turn signal bulb, weird things happen. The real question then is which ground and where is it.

Keep us posted!

Quote:
Originally Posted by Vinsanity View Post
I would think that a bad ground would stop the motor from working entirely--not send them dancing up and down. But yeah, I suppose I should eliminate that. Thanks.
Reply With Quote
  #14  
Old Yesterday, 08:02 PM
Karting
Not Subscribed
 
Join Date: Mar 2010
Location: Hill Island
Full Name: Paul XXXcX
Posts: 189
Quote:
Originally Posted by Saabguy View Post
A bad ground could give you a ground loop where the current flows backward through something. Like putting in the wrong type of turn signal bulb, weird things happen. The real question then is which ground and where is it.

Keep us posted!
Exactly, either find if there is one towards the motors or consult the diagram.

Back in the day, there was odd circuitry going on, like window regulators in the 60s that were permanently on 12V and you'd switch one or the other winding onto ground, depending which direction you'd go.
Reply With Quote
  #15  
Old Yesterday, 08:53 PM
Formula 3
Not Subscribed
 
Join Date: Sep 2007
Location: Suffolk England
Full Name: Tony
Posts: 1,846
On my car I did most of the things you have tried but eventually I stopped and looked at the problem In greater detail.

What you have are two motors that drive the pods up and down via linkages, when somebody operated the switch while I looked at the linkage movement I noticed a lot of sloppiness in the arms and rose joints.

After removing and fixing the worn out bits I reassembled them.

If not set up correctly the motors will just keep turning on a continuous cycle loop as they cannot find their off / on position, the motor has to move 180 degrees to switch on (say at 12 o clock) and then 180 degrees to switch off ( say 6 o clock) If it passes these points then it just rotates to the next position and so the problem just continues, hence the winking of the headlights.

To solve the problem I adjusted the linkages when when the motor rotates 180 degrees each time, they now work perfectly.

Be extremely careful with fingers, the motors are powerful.
Reply With Quote
  #16  
Old Yesterday, 09:30 PM
Karting
Not Subscribed
 
Join Date: Sep 2013
Location: Jacksonville,Florida
Full Name: "VD"
Posts: 100
Quote:
Originally Posted by TonyL View Post
On my car I did most of the things you have tried but eventually I stopped and looked at the problem In greater detail.

What you have are two motors that drive the pods up and down via linkages, when somebody operated the switch while I looked at the linkage movement I noticed a lot of sloppiness in the arms and rose joints.

After removing and fixing the worn out bits I reassembled them.

If not set up correctly the motors will just keep turning on a continuous cycle loop as they cannot find their off / on position, the motor has to move 180 degrees to switch on (say at 12 o clock) and then 180 degrees to switch off ( say 6 o clock) If it passes these points then it just rotates to the next position and so the problem just continues, hence the winking of the headlights.

To solve the problem I adjusted the linkages when when the motor rotates 180 degrees each time, they now work perfectly.

Be extremely careful with fingers, the motors are powerful.
I did think to check the linkages for slack--though I only did so when they were static. Everything seemed very firm, but I didn't watch them closely in action. It will probably be a few days before I get back to the garage and start messing with it again, and I will recheck those. Thanks.
Reply With Quote
Non-Sponsor Ads
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -5. The time now is 07:32 AM.


FerrariChat.com has no association with Ferrari S.p.A.
vB Ad Management by =RedTyger=

ShowCase vBulletin Plugins by Drive Thru Online, Inc.