Skip to main content ↑ ↓
Topic: Rear lamp indicator light (Read 2125 times) previous topic - next topic

Rear lamp indicator light

My rear lamp indicator light came on tonight.  I checked all the lights and they seem fine. Is there something that triggered this? Is there something I can do to turn this light off without disconnecting the warning light?  Like I said, everything works even the reverse and plate lights. Don't know why this warning light is on. Any help or advice would be appreciated.

Rear lamp indicator light

Reply #1 –
on your "system sentry"?

the item in the lower part of your center dash?

take your bulbs out of the rear and one by one inspect them especially the double filliment bulbs.
next thing i would do is pull off the battery postitive cable, wait a couple minutes then hook back up and see if that clears the fault.

Rear lamp indicator light

Reply #2 –
It only checks the rear parking lights and brake lights.
When does the lamp out warning light come on?

SAFETY FIRST: If you ever want to disconnect the battery, always disconnect the NEGATIVE battery cable.

Rear lamp indicator light

Reply #3 –
Yes, it is the light on the system sentry.  I disconnected the negative battery cable for about 10 mins and reconnected but its still on. It only comes on when the key is in the "on" position with the lights on. I'm gonna check the bulbs when I have more time but everything is working.

Rear lamp indicator light

Reply #4 –
Ok, that makes it a parking light problem. Look at them closely to see if one is dimmer than the rest.
When you check the bulbs, make sure they are all the same part number.

Rear lamp indicator light

Reply #5 –
Quote from: softtouch;406486
Ok, that makes it a parking light problem. Look at them closely to see if one is dimmer than the rest.
When you check the bulbs, make sure they are all the same part number.

Thanks. I'll check that out. Although they all look sort of dim. Maybe I'll just replace all of them and save myself the hassle of trying to decide which one is dimmer than the other lol.

Rear lamp indicator light

Reply #6 –
careful also,, i noticed with some of these sockets, "you can" insert and rotate the bulb into the socket even though its backwards.
pay attention to your key way slots on the socket as compared to the bulb.

Rear lamp indicator light

Reply #7 –
Will do! Thanks!

Rear lamp indicator light

Reply #8 –
This system doesn't have any memory, so unplugging the battery is USELESS. The system works ONLY with 1157 light bulbs. No 2057, P21/5W, LEDs...

It measures the voltage drop on the resistance cables. If it's lower, than the preset value, it turn the warning light on. That's all. It's just a stupid comparator. Nothing else.

Rear lamp indicator light

Reply #9 –
Hey guys, I'm having a similar problem but with the "Low Fuel" light. Except with mine, the light flickers on and off sometimes and I can hear the flickering. It stays on even after refueling
1987 Ford Thunderbird Turbo Coupe ~ STOCK

Rear lamp indicator light

Reply #10 –
buttstuffog gauges or electronic cluster?

Rear lamp indicator light

Reply #11 –
Quote from: Trinom;406518
This system doesn't have any memory, so unplugging the battery is USELESS. The system works ONLY with 1157 light bulbs. No 2057, P21/5W, LEDs...

It measures the voltage drop on the resistance cables. If it's lower, than the preset value, it turn the warning light on. That's all. It's just a stupid comparator. Nothing else.

 
Yes, our indicator lights are useless and I wish they were in the cluster. Low washer fluid, never used. Headlamp out, never used (and you can see if one is out...), rear lamp out, useful for stock but not with sequencers, leds, etc, low fuel, I can see that on the gauge, and I don't remember what the other two are.

What does the actual checking though? From what I can see, it looks like system sentry only turns the lights on and that the checks are done elsewhere in the vehicle. What checks the bulb wires for resistance?
1988 Thunderbird Sport

Rear lamp indicator light

Reply #12 –
Quote from: Seek;409341
Yes, our indicator lights are useless and I wish they were in the cluster. Low washer fluid, never used. Headlamp out, never used (and you can see if one is out...), rear lamp out, useful for stock but not with sequencers, leds, etc, low fuel, I can see that on the gauge, and I don't remember what the other two are.

What does the actual checking though? From what I can see, it looks like system sentry only turns the lights on and that the checks are done elsewhere in the vehicle. What checks the bulb wires for resistance?
Not all of those indicators work the same.
The lamp out warning has a resister wire in series with the lights. There is about a 1/2 volt voltage drop across the resistor wire with good bulbs. With a blown bulb there is less current flow in the circuit and therefor less voltage drop across the resistor wire.
The warning module detects this lower voltage drop.

Rear lamp indicator light

Reply #13 –
Quote from: BlueBird1987;409293
Hey guys, I'm having a similar problem but with the "Low Fuel" light. Except with mine, the light flickers on and off sometimes and I can hear the flickering. It stays on even after refueling

The light is controlled by a warning module. The inputs to the module are the fuel gauge sender and the 5 volts from the instrument cluster IVR.
The only thing I can think of that may have a sound would be the IVR. The IVR 5 volts also goes to the fuel gauge, the temp gauge and the oil pressure gauge. Do these gauges behave funny when the light is blinking?