Technical => Electrical Tech => Topic started by: Jays88Bird on January 07, 2013, 10:12:09 PM
Title: Rear lamp indicator light
Post by: Jays88Bird on January 07, 2013, 10:12:09 PM
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.
Title: Rear lamp indicator light
Post by: jcassity on January 08, 2013, 01:02:36 AM
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.
Title: Rear lamp indicator light
Post by: softtouch on January 08, 2013, 02:25:37 PM
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.
Title: Rear lamp indicator light
Post by: Jays88Bird on January 08, 2013, 02:33:09 PM
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.
Title: Rear lamp indicator light
Post by: softtouch on January 08, 2013, 02:53:00 PM
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.
Title: Rear lamp indicator light
Post by: Jays88Bird on January 08, 2013, 02:57:01 PM
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.
Title: Rear lamp indicator light
Post by: jcassity on January 08, 2013, 04:04:32 PM
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.
Title: Rear lamp indicator light
Post by: Jays88Bird on January 08, 2013, 04:06:30 PM
Will do! Thanks!
Title: Rear lamp indicator light
Post by: Trinom on January 08, 2013, 05:15:09 PM
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.
Title: Rear lamp indicator light
Post by: BlueBird1987 on February 13, 2013, 09:40:09 PM
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
Title: Rear lamp indicator light
Post by: softtouch on February 14, 2013, 01:31:35 AM
buttstuffog gauges or electronic cluster?
Title: Rear lamp indicator light
Post by: Masejoer on February 14, 2013, 01:35:21 PM
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?
Title: Rear lamp indicator light
Post by: softtouch on February 15, 2013, 01:06:32 PM
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.
Title: Rear lamp indicator light
Post by: softtouch on February 15, 2013, 02:34:23 PM
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?
Title: Rear lamp indicator light
Post by: Trinom on February 15, 2013, 05:36:44 PM
You are wrong - oil light is independent from oil pressure gauge. It has it's own oil level switch.
Title: Rear lamp indicator light
Post by: softtouch on February 15, 2013, 11:27:26 PM
Quote from: Trinom;409418
You are wrong - oil light is independent from oil pressure gauge. It has it's own oil level switch.
I did not say anything about the low oil light. I said the oil pressure gauge uses the IVR voltage.
Title: Rear lamp indicator light
Post by: jcassity on February 17, 2013, 12:19:56 PM
Quote from: softtouch;406484
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.
i was wondering what you meant,, sorry such a late reply. the diagrams and evtm say the headlamps are included.
Title: Rear lamp indicator light
Post by: jcassity on February 17, 2013, 01:11:59 PM
I am looking at the following pages in the 1987EVTM for.........
pg 120-theory of operation
pg 119 of for rear turn and stop (hazard) lamps --->> I am recommending to swap out your existing hazard and turn flashers which are mounted back to back on your fuse panel. The resistance wires leading out to these lights are in parallel with the warning indicator system, the hazard/turn flashers are common to both. More preciesly i would suggest you swap the turn flasher first as it is used more often. If the contacts inside the flasher are worn/burned, this will effect the volage drop the warning system is using to compare.
pg 91 for rear park lamps
Title: Rear lamp indicator light
Post by: jcassity on February 17, 2013, 01:14:01 PM
on last question,, Do you happen to have a sequencial tail lamp system?
Title: Rear lamp indicator light
Post by: softtouch on February 17, 2013, 01:52:13 PM
Quote from: jcassity;409539
i was wondering what you meant,, sorry such a late reply. the diagrams and evtm say the headlamps are included.
His REAR lamp out light comes on with the parking lights.
Title: Rear lamp indicator light
Post by: BlueBird1987 on February 23, 2013, 01:39:28 PM
Quote from: softtouch;409411
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?
These other gauges don't behave funny when my light is flickering, it all acts normal.
Title: Rear lamp indicator light
Post by: softtouch on February 23, 2013, 05:27:48 PM
This post is for jays88bird, the OP.
Time to make some voltage readings. Have you identified the four brake/tail light bulbs? On the right side they have an orange wire and a brown wire. On the left it's a green and a brown. Brown is the parking lights. With the parks on, measure the voltage from each of the four parking light brown wires to ground.
All of the "other" lights, side marker,license plate,inner running lamp, all have a brown wire. I want you to measure the voltage between one of these "other" lamps brown wire and the four brown wires to the parks. Put the positive meter lead on the "other" lamp and the ground lead on each of the parks. These will be less than one volt. Let us know the readings.
bluebird1987, maybe you should start your own thread. Mixing different cars in the same thread is confusing, at least for me.
Title: Rear lamp indicator light
Post by: ABird on February 23, 2013, 06:09:07 PM
Wasn't the 2nd question about the "low fuel" light?? Completely controlled by low fuel warning module, it appears.
Title: Rear lamp indicator light
Post by: jcassity on February 24, 2013, 10:27:25 AM
softtouch~ its a little hard to explain to someone how to do a difference of potential test, you wrote that up pretty good.