Home 
Home Search search Menu menu Not logged in - Login | Register
> Jensen Healey & Jensen GT Tech > Electrical & Instruments > Location of reverse light switch

 Moderated by: Greg Fletcher
New Topic Reply Printer Friendly
Location of reverse light switch  Rating:  Rating
AuthorPost
 Posted: 08-17-2005 05:43 pm
  PM Quote Reply
1st Post
edward_davis
Member


Joined: 07-06-2005
Location: Eugene, Oregon USA
Posts: 162
Status: 
Offline
Can anyone give me an idea where to find the reverse light switch on the 4-speed gearbox?  I've looked at the diagram in the manual but can't find any evidence of it.  Also, I would appreciate any information on the best places to start looking for faults in the reverse-light circuit.

Sorry if this is posted multiple times: my browser flaked out.

Thanks

Back To Top PM Quote Reply  

 Posted: 08-17-2005 06:58 pm
  PM Quote Reply
2nd Post
Mark Rosenbaum
Member


Joined: 03-12-2005
Location: Kingman, Arizona USA
Posts: 532
Status: 
Offline
For 4-speed cars, the switch is item #28 on the Gearbox Controls drawing.  It's located far forward on the left side of the transmission top cover, and is rather hard to get to.

Troubleshooting is pretty simple.  Power from Fuse #1 runs to the Ignition Fused Junction under the dash, and thence to one of the switch contacts.  The other switch contact connects directly to the sockets for the two backup lights.  The switch should be closed when the gearshift lever is moved into reverse, and open otherwise.

If the switch works fine when removed from the transmission, but not when installed, most often that's because the washer between the switch and the transmission top cover is the wrong thickness.  Occasionally you'll find excessive wear either to the part in the shift linkage that activates the switch, or in the ball in the switch on which the linkage presses, or both -- for which the cure is a thinner washer under the switch.

The attached drawing may help.

 

Attachment: Bacjkup switch.jpg (Downloaded 217 times)

Back To Top PM Quote Reply

 Posted: 08-17-2005 10:32 pm
  PM Quote Reply
3rd Post
Ron Mau
Member
 

Joined: 03-14-2005
Location: Davenport, Iowa USA
Posts: 61
Status: 
Offline
I found that the ground at the light wasn't quite good enough to ground the light so Iwould check there also. Use a short piece of wire and ground the lamp socket and see if that solves your problem.

Ron Mau

Back To Top PM Quote Reply  

 Posted: 10-23-2013 07:22 pm
  PM Quote Reply
4th Post
dwalls1
Member
 

Joined: 04-11-2008
Location: Bloomfield, New Mexico USA
Posts: 207
Status: 
Offline
My back up lights quit working. Connecting the two wires together at the switch the on the transmission lit the lights. I removed the switch and bench tested it and it seems to work fine. Reinstalled it less the spacer washer and still no lights. What next? Is it possible the switch is still the culprit? Can the switch button be extended, say with a glob of weld material. That would, of course, invite disaster if the glob broke off. Any responses very much appreciated.

Back To Top PM Quote Reply

 Posted: 10-23-2013 07:29 pm
  PM Quote Reply
5th Post
Jensen Healey
Super Moderator


Joined: 03-11-2005
Location: San Anselmo, California USA
Posts: 983
Status: 
Offline
Yes, you need to test the switch itself.

Back To Top PM Quote Reply  

 Posted: 10-23-2013 07:41 pm
  PM Quote Reply
6th Post
dwalls1
Member
 

Joined: 04-11-2008
Location: Bloomfield, New Mexico USA
Posts: 207
Status: 
Offline
Thanks for the prompt reply. I did test the switch with a power source in series with a test light. Do I need to replace it with a new switch to get a definitive test?

Back To Top PM Quote Reply

 Posted: 10-24-2013 12:32 am
  PM Quote Reply
7th Post
Jensen Healey
Super Moderator


Joined: 03-11-2005
Location: San Anselmo, California USA
Posts: 983
Status: 
Offline
Sounds like it's time to check the nub on the linkage.

Back To Top PM Quote Reply  

 Posted: 10-24-2013 02:35 am
  PM Quote Reply
8th Post
dwalls1
Member
 

Joined: 04-11-2008
Location: Bloomfield, New Mexico USA
Posts: 207
Status: 
Offline
That looks like I'd have to pull the tranny as,"therein lies the nub"

Back To Top PM Quote Reply

 Posted: 10-24-2013 03:21 am
  PM Quote Reply
9th Post
Jensen Healey
Super Moderator


Joined: 03-11-2005
Location: San Anselmo, California USA
Posts: 983
Status: 
Offline
It is interesting that removing the washer didn't allow the switch to operate. How does the ball contact point on the switch look?
Maybe you could use a piece of wire or a bolt to measure the switch seat to nub distance.
Then compare with the male end of the switch body to make sure it's being engaged.
It may be slop in the shifter isn't moving the nub into position.

Back To Top PM Quote Reply  

 Posted: 10-24-2013 12:12 pm
  PM Quote Reply
10th Post
dwalls1
Member
 

Joined: 04-11-2008
Location: Bloomfield, New Mexico USA
Posts: 207
Status: 
Offline
It does seem strange that the nub would be the problem. The ball end looks good. I may play with it some more when I get a chance. It's pretty fiddly as I am working "blind" up in that tunnel, but I may probe that hole and see if I can feel any thing inside there. The switch could still be fooling me, so I will take it to work and blow compressed air in it, perhaps clean the contacts or something.

Back To Top PM Quote Reply

 Posted: 10-25-2013 01:28 am
  PM Quote Reply
11th Post
dwalls1
Member
 

Joined: 04-11-2008
Location: Bloomfield, New Mexico USA
Posts: 207
Status: 
Offline
Tested the switch several more times today, with inconsistent results. Ordered a new switch and I am confident that that is the problem.

Back To Top PM Quote Reply  

 Posted: 10-31-2013 01:19 am
  PM Quote Reply
12th Post
dwalls1
Member
 

Joined: 04-11-2008
Location: Bloomfield, New Mexico USA
Posts: 207
Status: 
Offline
Installed the new switch with the spacer washer, lights work fine. I had retested both the old and new switches with the multi meter and got results that made me certain that the old switch was the problem.

Back To Top PM Quote Reply

 Posted: 08-25-2017 08:27 pm
  PM Quote Reply
13th Post
JPJH
Member
 

Joined: 12-28-2015
Location: Fitchburg , Massachusetts USA
Posts: 31
Status: 
Offline
I wanted to add a few comments having just done this. My backup lights were out and I spent a bit of time tracing wires. The easiest thing I found was if you jack the car and place completely on jack stands it's easy to get to the switch. First step was to jump the switch testing the complete circuit, when the lights worked I pulled the switch, 1-1/16 deep socket and replaced it.

Back To Top PM Quote Reply  

Current time is 11:30 am  
> Jensen Healey & Jensen GT Tech > Electrical & Instruments > Location of reverse light switch Top




UltraBB 1.172 Copyright © 2007-2011 Data 1 Systems