Stop Lamp Circuit Dead?

[secondq]

Read thru the stop lamp issues posted here, I may have a different issue

1. Sopt lamps do not turn on when the brake padel is pressed. Only the center lamp in the rear window lights up.

2. The instrumentation panel does not warn "Stop Lamp Inoperative" - infact, the computer panel says "OK". Kind of funny

3. However; when brake is pressed rear stop lamp shows no light. I actually got stopped by a cop today and he issued a work order for me citing this can cause accidents - could not agree more, the computer panel conitnues to show "OK"

4. I replaced all rear stop light bulbs with Sylvania 1157LL bulbs and no change. I know about the dealer bulbs - will be ordering them tomorrow - but this one looks weird - I do not get the "Stop lamp inoperative" warning as others reported, instead mine shows "OK" but no stop lights come on.

5. The info I have gathered reading the forum so far is that (1) dealer bulbs (2) replace the Assembly - $15 a piece or so.

6. Anything I can check to see if the circuit is complete. I read thru the service manual and it talks about the Stop light sensor check - am I supposed to check to volts with the sensor connected or disconnected from the harness? If I take the sensor out, I am not getting any voltage b/w the points the manual says I should see "12v" when all bulbs are good and "2.5v" when one or more stop lamp bulbs are removed. This may be my issue - however; I wanted to make sure I ma doing the test correctly - I start the car, press the brake, disconnect the sensor (in back trunk) and then check for voltage - I get no volatge on the terminals there.

Thanks for any help .

[DAEDALUS]

What year/model car?

[secondq]

92Q45 -

I tested with a new bulb socket (dsiconnected the original bulb assembly), the back light lamp comes on (when the light is turned on) however; the brake light did not -

I strongly suspect the the circuit is broken to light up the brake lamps - just no juice in that path.

I have checked the fuse (15a) in the driver side fuse box - seems ok, if I remove it the rear window brake light goes out as well - so it is working as expected - the path of circuit to the rear stop lamps seems to be not connected for some reason - kind of weird.

Thanks

[Q45tech]

The voltage for rear lamps loops thru the lamp sensor assembly [to measure the current draw [via a current shunt......voltage drop] on each group of lamps.

Excess current from bad bulbs or sockets can melt the solder holding the SHUNTS [multiple] to pc board inside the sensor assembly.

The electronics [inside sensor assembly] can also fail feeding an OK voltage to the display.............usually happens when non oem [not to standard] bulbs are used as replacements.

Years ago Nissan had a complete boxed kit of replacement bulbs for Q, haven't seen this in years.

For those junkyard users.....there are 2 different models of rear lamp sensor assembly.....1 for standard/active and one for Q45t!

If the rear window or spoiler brake lights work and all bulbs and sockets are good......always the sensor module.

[secondq]

Dennis - thanks for the help.

What is the best route to buy the sensor assembly? I assume this is the purple color module in the back trunk.

Is there a way to test the sensor?

Thanks
Modified by secondq at 9:13 PM 2/14/2005

[secondq]

I busted open the stop & Tail lamp sensor and found the solder to be loose where one of the pins connected to the PCB - fixed with solder iron and bingo - the lights are working back again.

Thanks Dennis for the pointer.

For others in same boat, just pop open the black holder and the PCB slides out, then you can inspect to see if anything is burnt or loose.


Modified by secondq at 10:30 PM 2/14/2005

[Q45tech]

Change the rear lamp sockets and install at least Sylvania LL bulbs all around or it will just happen again.

[secondq]

Dennis - did this already (kind of) - the bulbs were are replaced with Sylvania 1157LL all around. The assembly is on its way from Joe.

Thanks again

[cwestin_95s14]

My 01 I30 is in the dealership for repair because of the same issue. The brake lights and the light on the spoiler do not come on when i apply the brakes.

Emad

[Q45tech]

Bulbs change resistance with age as the tungsten boils off making some spots of filament coil thinner and thinner and thinner till they finally fail.

Waiting till bulbs burnout before changing is never the best idea.......usually a bad time -------like at night after a ticket.

Looked at my bulbs yesterday everyone [to varying degrees] has the telltail depression on the bottom tip from overheating..........time to buy and change all rear bulbs before the sockets get fouled........about every 2 years seems the norm for my application [light on ratio].......brake application per mile have increased since many are traffic vs interstate miles now and more night usage.

What's $12 every 2 years........<half of a percent of the $3,000 budget.Cheaper than sockets and the sensor module or the ticket.

How many keep a spare set [at least one of each type] at home or in the Q? Seems normal to buy in advance so you don't have to waste gasoline on a special trip........just for a bulb.

[ballrific12002]

hey you seem to know a lot about this problem. So my Q was doing the same thing with the whole stop lamp inoperative message. I changed the bulb for it and the message went away but i still have this problem with my dash lights and my radio illumination dimming when i hit the brakes. Ive blown fuses both inside the car and under the hood with this problem multiple times. I can drive with the lights dimming for a couple days then the illumination fuse blows or the lighting fuse under the hood blows. If you or anybody can offer any help before i get a pulled over thatd be sweet.

[manassas_hokie]

I took out my sensor and inspected it since i had the same problem with the brake lights out but the lamp in the window still working and i cannot detect any loose connections or see any physical damage to the circuit. I did observe an open connection in the pins with my voltometer when pairing the pins in the front. does this mean that the sensor is broken? im not much of an electrician so i did not no how to trouble shoot the problem

[MeatRo]

I'm having a problem with this "stop lamp inoperable". But all my lights work perfectly, I checked the little pink box for shorts or anything obvious, nothing.

Now, I did have to change a bulb on the car (I just bought it) and the inside passenger bulb socket was shorted out. I cleaned it up and got it working properly, but could this have damaged the little pink box (sorry, I'm not hip to the Q45 lingo, LoL)?

[Q45tech]

If you observe the interior of lamp sensor you will note 3 small + 2 large loops of tinned wire these represent the 5 individual lamp circuits that are checked [monitored] by the device.

Just one of the dozens of modules one collects for future failures:FPCULamp monitorPS steering speed controllerECUTCUMAFCASIgnitorHVAC computer

CoilsInjectorsKS + harness

[Q451990]

hey you seem to know a lot about this problem. So my Q was doing the same thing with the whole stop lamp inoperative message. I changed the bulb for it and the message went away but i still have this problem with my dash lights and my radio illumination dimming when i hit the brakes. Ive blown fuses both inside the car and under the hood with this problem multiple times. I can drive with the lights dimming for a couple days then the illumination fuse blows or the lighting fuse under the hood blows. If you or anybody can offer any help before i get a pulled over thatd be sweet.

The lights dimming certainly sounds like a short between your park lights and brake lights. Check to see if the front park lights come on at the same time...

It's pretty likely that you have a socket that is defective, but try removing each bulb one at a time to see if you can narrow it down. If you have any black charred looking sockets - just replace the assemblies...

Good luck!

Heath

[maxnix]

I'm having a problem with this "stop lamp inoperable". But all my lights work perfectly, I checked the little pink box for shorts or anything obvious, nothing.

Now, I did have to change a bulb on the car (I just bought it) and the inside passenger bulb socket was shorted out. I cleaned it up and got it working properly, but could this have damaged the little pink box (sorry, I'm not hip to the Q45 lingo, LoL)?

OEM, Sylvania LL, or cheap Chinese imposters imported by American retailers like NAPA, AutoZone, PepBoys, etc?

[rockykennel's]

i have 1990 infiniti q45 in the stop lamp inoperative came on and it cut my car off. How do i go about all this?

[Q45man1]

Check your bulb, socket and sensor. I had the same issue before and I ended up replacing the brake sensor. This sensor will cost you $80.00+ new from Infiniti of Scottsdale. I had the thread before how to check the sensor voltage.

[fixer]

did you have the dimming problem before you replaced the bulb? Lots of times I have seen people put a single element bulb in a socket for a dual element bulb. this will cause a short between brake light circuit and park light circuit. you should double check the most recently replaced bulbs.

[tim1000]

Had brake lights out in the rear, but light in window still worked. So I tapped into the rear window light that worked to give me lights for the lamps. Well, that apparently was a bad idea because now non of the brake warning lights work. Any ideas? It seems from what I've been reading on the forum that I should have replaced the stop light sensor which I didn't know existed and now that I do, I have no idea what it looks like and where it is on my 1991 Q45.

[Q451990]

Check out the factory service manual, available at www.nicoclub.com/FSM/ for the exact location. It's in the trunk under the finisher around the trunk latch on the body of the car (not the lid). It's about the size of a large relay and is usually a pink color.

Heath

[tim1000]

did you have the dimming problem before you replaced the bulb? Lots of times I have seen people put a single element bulb in a socket for a dual element bulb. this will cause a short between brake light circuit and park light circuit. you should double check the most recently replaced bulbs.

Nope.

[tim1000]

did you have the dimming problem before you replaced the bulb? Lots of times I have seen people put a single element bulb in a socket for a dual element bulb. this will cause a short between brake light circuit and park light circuit. you should double check the most recently replaced bulbs.

Nope. Just lost them completely accept the light in the rear window. I tapped into the rear window brake light which turned into a bad idea. Now I have nothing. Still have power in the fuse box, but no power at the sensor connector.