Back up lights
03-04-2011, 02:07 PM
#1
Racer
Thread Starter
Back up lights
My recently acquired LT4 has been Safety Checked, Emission Checked and plated, ready for some open roads once the weather clears (soon). I noticed that my back up lights are not working. The fuse is good and the bulbs appear to be OK. Has anybody run into the same situation? My next guess is the switch/relay that should be located somewhere around the transmission shifter. It's not a huge deal for me however I'll be installing a Hurst short throw shifter in the next month or so and that may be good time to resolve the non functioning back up lights. If anyone has any suggestions, ideas please let me know. Thanks, Peter.
03-04-2011, 03:05 PM
#2
Drifting
You say the bulbs appear good, you could test them to be sure. Check the bulb sockets for corrosion, and while you're at it, test the sockets to see if there is power there when the trans is in reverse. The b/u light switch is on the trans, left side high and forward near the bell housing. Look for power to the switch and power out when the trans is in reverse.
03-04-2011, 03:28 PM
#3
Racer
Thread Starter
Thanks for the fast response. While both bulbs look good, your right, I should test them, it's just that they're both out. There wasn't any corrosion. I'll get a tester out. Thanks.
03-04-2011, 05:20 PM
#4
Team Owner
Do the two lights on the rear quarter panels come on when in Reverse? Also the ignition key has to be in the ON position.
If the side lamps don't come on either, then I would check the switch on the trans as mentioned. The wires going to the switch should be dark blue and light green. The light green wires go to the four lights so providing a 12v source to the light green wire will check the bulbs.
If the switch is good, with the ignition switch ON and the shifter in Reverse, there should be 12v at the switch terminal where the green wire attaches. There should be 12v at the dark blue wire with the ignition ON.
Also check the Turn/Backup fuse in the fuse panel. It's a 15A fuse.
If the side lamps don't come on either, then I would check the switch on the trans as mentioned. The wires going to the switch should be dark blue and light green. The light green wires go to the four lights so providing a 12v source to the light green wire will check the bulbs.
If the switch is good, with the ignition switch ON and the shifter in Reverse, there should be 12v at the switch terminal where the green wire attaches. There should be 12v at the dark blue wire with the ignition ON.
Also check the Turn/Backup fuse in the fuse panel. It's a 15A fuse.
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yakmastermax (01-24-2023)
03-04-2011, 10:31 PM
#5
Racer
Thread Starter
c4cruiser, thanks...fuse is good. Will check out qtr. panel lights. Will get to the transmission area to check out juice before and after the switch in a month or so. Appreciate your help.
03-05-2011, 04:40 AM
#6
Safety Car
Do the two lights on the rear quarter panels come on when in Reverse? Also the ignition key has to be in the ON position.
If the side lamps don't come on either, then I would check the switch on the trans as mentioned. The wires going to the switch should be dark blue and light green. The light green wires go to the four lights so providing a 12v source to the light green wire will check the bulbs.
If the switch is good, with the ignition switch ON and the shifter in Reverse, there should be 12v at the switch terminal where the green wire attaches. There should be 12v at the dark blue wire with the ignition ON.
Also check the Turn/Backup fuse in the fuse panel. It's a 15A fuse.
If the side lamps don't come on either, then I would check the switch on the trans as mentioned. The wires going to the switch should be dark blue and light green. The light green wires go to the four lights so providing a 12v source to the light green wire will check the bulbs.
If the switch is good, with the ignition switch ON and the shifter in Reverse, there should be 12v at the switch terminal where the green wire attaches. There should be 12v at the dark blue wire with the ignition ON.
Also check the Turn/Backup fuse in the fuse panel. It's a 15A fuse.
03-05-2011, 06:55 AM
#7
Melting Slicks
Member Since: Nov 2005
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The backup or reverse lamp switch seldome fails but is often replaced. The switch makes electrical contact through a steel ball. This provides a ver small contact area...which over time corroides and no longer passes current.
What is usually required is taking the switch out and moving this steel ball so that a different area is used. Cleaning it with some contact cleaner works also. Then re-install it. Will work fine for many years.
Trouble is getting the switch out is still a PITA. On manual trans the slave cylinder must be unbolted from the bell housing in order to get a normal wrench on the switch. I think the auto trans has the switch in the console.
Oh and switch is quite expensive too.
What is usually required is taking the switch out and moving this steel ball so that a different area is used. Cleaning it with some contact cleaner works also. Then re-install it. Will work fine for many years.
Trouble is getting the switch out is still a PITA. On manual trans the slave cylinder must be unbolted from the bell housing in order to get a normal wrench on the switch. I think the auto trans has the switch in the console.
Oh and switch is quite expensive too.
03-05-2011, 10:56 AM
#8
Racer
Thread Starter
LannyL81, good info. As I've mentioned in an earlier post, I'm hoping to get to the switch when I install the Hurst shifter. In the meantime, I'll hardcopy this thread and shove it inside the Vette for when I'll need it. I see your in AZ. My wife and I love AZ and have a home there along with some great friends and neighbors. Thanks again.
03-05-2011, 01:03 PM
#9
Melting Slicks
In my '87 auto there is a shift lever jiggle issue---i.e. if the reverse lights aren't on, jiggle the lever & they will be. I was reading through the FSM & it said this was adjustable but the adjustment was none too clear with just a casual read. I'm not sure any of this is relevant to your manual transmission but, if you haven't already, you might check the FSM to see if your's is adjustable too.
03-05-2011, 01:12 PM
#10
Tech Contributor
The backup switch is located on the top left side of the transmission. It's a PIA to reach, but if you remove the clutch slave cylinder (5 minute job), it gives you some wiggle room for your arm. As I recall from the last time I did one "in car", a socket won't fit between the transmission and the tunnel so you'll need a wrench.
Since the fuse is good and assuming the bulbs are good...
A simple test is to pop the electrical connector free from the switch, jumper the two pins, turn the ignition key to "run", and see if the backup lights are illuminated. If so, then you've verified it's the switch. 99 times out of 100 that's the case.
Since the fuse is good and assuming the bulbs are good...
A simple test is to pop the electrical connector free from the switch, jumper the two pins, turn the ignition key to "run", and see if the backup lights are illuminated. If so, then you've verified it's the switch. 99 times out of 100 that's the case.
03-05-2011, 08:57 PM
#11
Racer
Thread Starter
And we wonder what it is we like about this Forum? Solid advice in a timely manner from like minded Corvette buddies. Does it get any better? Thanks guys.
I wish I had access to this kind of help in the early 80's when I bought my first Corvette.
I wish I had access to this kind of help in the early 80's when I bought my first Corvette.
03-06-2011, 07:10 AM
#12
Melting Slicks
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I have the Hurst shifter as well in my '96....I sure like it. It does take more effort to shift it, especially reverse, but I like it. I had the B&M for awhile...but it too short and notchy. You will like the Hurst. It is not alot of fun installing it though....that rubber boot is difficult to hold back....need three hands when there is only room for one.
AZ is nice place to live weather wise anyways. Where do you have your 2nd home at?
AZ is nice place to live weather wise anyways. Where do you have your 2nd home at?
03-07-2011, 04:55 PM
#14
Racer
Thread Starter
LannyL81, I suspect you may not have gotten my PM...I think I screwed. Yes, 2nd home in Scottsdale around the 101/Via Linda area if your familiar with the Phoenix area. Your just outside Tuscon, aren't you? Did you have to move the exhaust pipes out of the way when you installed your Hurst shifter? Thanks.
03-07-2011, 04:59 PM
#15
Tech Contributor
LannyL81, I suspect you may not have gotten my PM...I think I screwed. Yes, 2nd home in Scottsdale around the 101/Via Linda area if your familiar with the Phoenix area. Your just outside Tuscon, aren't you? Did you have to move the exhaust pipes out of the way when you installed your Hurst shifter? Thanks.
03-07-2011, 11:35 PM
#19
Tech Contributor
Not unexpected in 15+ year old cars.
03-08-2011, 12:32 AM
#20
Instructor
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when I got my 94 (6 speed) the reverse lights didn't work replaced the switch on the trans and problem solved, I was told the reverse light switch is a common problem on the zf6. Kind of hard to get to but not that bad.