911 SC reversing light problem
06-07-2006, 06:38 PM
#17
Rennlist Member
85: The 915's reverse switch is located near the bottom, passenger side, of the nose of the trans. To access it you don't have to do much except raise the back of the car. This is better done on a hoist. If it's still there a rubber boot will cover the switch, you have to pull that off to see the switch.
Pete
Pete
06-07-2006, 07:48 PM
#18
Team Owner
I don't know how the wires mount to the switch but if you can somehow take off just the load side of the switch and the fuse doesn't bow,it isn't the switch.
06-07-2006, 08:08 PM
#19
Rennlist Member
The wire connectors are those old fashioned bullet style contacts that push into holes in the end of the switch. Many 356 connections were done with them, and they are a little more fragile than the typical male/female set up. The stripped wire fits into the connector and is held with a drop of solder.
Pete
Pete
06-07-2006, 08:10 PM
#20
Team Owner
Pete I think I know the type , my motorcycle uses them. If this is the case he shoul be able to disconnect the load wire independantly right ?
06-07-2006, 08:52 PM
#21
Rennlist Member
He can use needle nose pliers to pull it off it is separated from the wire. If it needs to be done, resolder the wire into the end off the bullet style connector. I used to wrap a small piece of electrical tape around one of the bullet connectors after I put it on . This was to prevent both connectors fron accidently touching and causing a short. Then push the rubber cover back over the unit. Always worked for me.
06-07-2006, 09:57 PM
#22
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85Cab, I developed the same problem you had after replacing the rear turn signal housing on my car. It seems after I hooked up the wires in my new tail light housing, I left one of the wires bent a little too close to the housing. After putting everything back together, the turn signals worked fine until I put it into reverse. The wires shorted out and blew the fuse. If you recently replaced any rear light bulbs, you might want to check the housing before pulling your hair out trying to diagnose the problem in the wrong place.
06-08-2006, 11:47 AM
#23
Rennlist Member
Yes, the hot (load) wire can be disconnected and taped off. George does bring up a great point, although I've never see a problem within a rear light housing it's entirely possible.
Pete
Pete
06-08-2006, 07:12 PM
#24
Team Owner
Actually Pete I meant the load side being the "cold " side. I think it's a terminology thing. The hot side ( power source) feeds the switch and to determine if his switch its truely bad he could disconnect the load ( device being powered side of the switch , in this case the lights) . He can then see if his fuse blows when he puts it in reverse. If it does it's the switch , but I doubt it will. Hey wait a minute were doing all the talking .. where is this 85 cab guy anyway with some results.. 
06-08-2006, 07:45 PM
#25
Rennlist Member
Ah, ha, now I understand, and it makes perfect sense. We never talked much about electrical problems at the shop, just fixing them gave us headaches!
Yeah, where is that 85cab guy, anyway?
Pete
Yeah, where is that 85cab guy, anyway?
Pete
07-10-2006, 02:05 PM
#27
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Sorry to duck out of the thread last month, I had some family emergencies to deal with.
I do have some additional questions, I pulled the rubber boot off of the switch and the bullet connectors out of the switch. All connectors are in good condition and solid. I have not yet tested for hot lead and thought one of you could tell me which wire is hot.
If in fact the switch needs to be replaced, the Bentley's manual states that transmission fluid will drain from the switch hole. How much fluid are we talking about. Does this suggest that the Carrerra should be jacked and placed on stands both front and back to prevent excess fluid from draining forward?
I do have some additional questions, I pulled the rubber boot off of the switch and the bullet connectors out of the switch. All connectors are in good condition and solid. I have not yet tested for hot lead and thought one of you could tell me which wire is hot.
If in fact the switch needs to be replaced, the Bentley's manual states that transmission fluid will drain from the switch hole. How much fluid are we talking about. Does this suggest that the Carrerra should be jacked and placed on stands both front and back to prevent excess fluid from draining forward?
07-10-2006, 02:14 PM
#28
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George, thank you for your comment. Interestingly enough, I did have a blown light in my rear right turn signal that I replaced; however, the reverse problem was symptamatic before I replaced the bulb. I took all of the turn signal housings out w/o disconecting any wires, cleaned them up and checked for shorts and could not see any problems.
Anythoughts on how to trouble shoot this will be greatly appreciated.
The little rubber bits (drain plug, wire socket plug and houseing seal) in both turn signals need to be replaced.
Anythoughts on how to trouble shoot this will be greatly appreciated.
The little rubber bits (drain plug, wire socket plug and houseing seal) in both turn signals need to be replaced.
07-10-2006, 03:08 PM
#30
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For clarification, I should remove the fuse for the back up lights. put a multimeter set on ohms ( resistance ) on the cold side of the fuse connector and a good ground point. When you put it in reverse AND USE TURNSIGNAL? the resistance value will drop to 0 ohms ( short) and then start to pop the bulbs out until the resistence increases. What should the resistence increase to?