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Need help with aftermarket warning lights

 
  #1  
Old 01-11-2019, 07:49 PM
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Need help with aftermarket warning lights

Hey guys, I'm sure some of you have been following my progress on the Autometer dash cluster project I've been doing.

Tonight I finally got the GPS hooked up for the speedo and both the sending units for the oil pressure and water temp.

After firing the truck up all the gauges are operating as they should.

However the problem exists with the low battery / low charge light and the engine light. Both are staying on.

The charge light will come on as soon as you move key to the accessory position and stays on after the truck is started.

The engine light only comes on the moment the truck is started but does not come on in the accessory position.

The engine light is ran to the Pink/Grey wire 658 Check Engine Input from EEC (Pin #9 from C251)

The charge light is ran to the Red/Light Green wire 904 Amp indicator Output (Pin #13 from C251) This is also the same wire that needs the switched 12v in order for the Alt to charge. Probably why the light is staying on due to the switched 12v?






Eddiec1564
subford

Thanks for all the help.
 
  #2  
Old 01-12-2019, 10:30 AM
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Any help would greatly be appreciated.
 
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Old 01-12-2019, 12:15 PM
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if the truck is running and the charge light is on , is your alternator charging, check your codes with your scanner, i suspect your alternator isn't charging due to the low resistance of the LED in the the charge indicator light. try swapping it out for the original bulb or test it with an incandescent bulb.
 
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Old 01-12-2019, 12:19 PM
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Originally Posted by MPP8405 View Post
if the truck is running and the charge light is on , is your alternator charging, check your codes with your scanner, i suspect your alternator isn't charging due to the low resistance of the LED in the the charge indicator light. try swapping it out for the original bulb or test it with an incandescent bulb.
It should be charging regardless though due to me running a switched twelve volt to it that supplies 12v when the ignition is in accessory or run.


Not only does the light have a built in resistor but the gauge says its charging as well.
The picture shows the gauge while the truck is running.

You can see in the pic just to the left of the steering wheel that the amp gauge is at 11. This is after ten minutes of the truck running.

What should my Amp gauge be at if the charge system is working properly?

Unless I'm thinking of this all wrong?
 
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Old 01-12-2019, 12:28 PM
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the bulb is part of the charge circuit, ans has a resistor inline with it: your volt gauge should be above 13.5V now when you built your cluster did you add that resistor back, maybe thats the issue?

 

Last edited by MPP8405; 01-12-2019 at 12:32 PM. Reason: need to add info
  #6  
Old 01-12-2019, 12:33 PM
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Originally Posted by MPP8405 View Post
the bulb is part of the charge circuit, ans has a resistor inline with it:

Ok. The way I'm thinking is that if the original cluster is no longer present it can no longer complete the circuit which is why I ran the switched twelve volt to it in order to give it the twelve volt signal it needs to charge.

Then being that the LG/R wire is duel function not just for the charge system but for the Low Charge/Low Battery warning light I was told to splice my warning light with built in resistor to it as well.

Thanks for the schematic.


 
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Old 01-12-2019, 12:38 PM
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exactly this is why i asked with the engine running use a multimeter and check your battery voltage, check on the OEM cluster if there is a resistor of that resistance in the circuit if you can unsolder it add it to your new wiring and see if your light goes out.
 
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Old 01-12-2019, 12:43 PM
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Originally Posted by MPP8405 View Post
exactly this is why i asked with the engine running use a multimeter and check your battery voltage, check on the OEM cluster if there is a resistor of that resistance in the circuit if you can unsolder it add it to your new wiring and see if your light goes out.
I see. Gotcha. Just figured the gauge would tell me if it wasn't putting out enough charge.

Im just not certain what the gauge should be at in normal operating conditions but to my understanding.....

Cars operate on a 12-volt electrical system. A fully charged battery should read about 12.5 volts when the key is in the ignition and turned partially, but the car's engine is not running. Look at the voltmeter while the engine is running. Readings of 14 to 14.5 volts on the gauge Should be normal.
 
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Old 01-12-2019, 12:47 PM
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BTW get a pic at a drivers view of your new gauge cluster and tach so we can see your progress Keep it up dude.
 
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Old 01-12-2019, 01:04 PM
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Originally Posted by MPP8405 View Post
BTW get a pic at a drivers view of your new gauge cluster and tach so we can see your progress Keep it up dude.
Id love too but I have to get these bugs worked out before I can put the dash back together and get a pic. This is the final step and I'm excited to get it complete and back together.

Just this morning I swapped out the headlight and wiper light to blue to match the gauges along with the HVAC control light. Matches perfectly.

Tomorrow im switching the dome light bulb out with a cool white LED bulb and clear cover as well. I'll be doing the same with the ash tray and glove box bulbs.
 
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Old 01-12-2019, 01:43 PM
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So if I had to get a 510 ohm resistor, what watts does it have to be.

So I don't have my meter. After searching for it I realized I lent it out to a friend a while back who no longer lives in my state.

I went out and ran the truck to full operating temp and the gauge did not move from 11. I turned the lights and heater on and it dropped down to just over ten and did not recover until the lights and heater were shut off. But it recovered very quickly.

Sound normal for our trucks?

Ive done a lot of research on this before I started the project and have talked with them about this exact situation. I copied how they did it because they didn't have any issues so I'm flustered at this point.
 
  #12  
Old 01-12-2019, 01:47 PM
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Originally Posted by Inside Man View Post


Id love too but I have to get these bugs worked out before I can put the dash back together and get a pic. This is the final step and I'm excited to get it complete and back together.

Just this morning I swapped out the headlight and wiper light to blue to match the gauges along with the HVAC control light. Matches perfectly.

Tomorrow im switching the dome light bulb out with a cool white LED bulb and clear cover as well. I'll be doing the same with the ash tray and glove box bulbs.
I've done the clear cover swap made a difference in light in the cab stock one was useless and yellowed . Mind you a hi lumen bulb helps too. When I add a auto dimming mirror with lights it should help me see in the cab better.
 
  #13  
Old 01-12-2019, 01:55 PM
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The resistors just get a 500 and a 10 ohm resistor in series and add it to your wiring to the lamp. Should be fine that way.
 
  #14  
Old 01-12-2019, 02:09 PM
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Originally Posted by MPP8405 View Post
The resistors just get a 500 and a 10 ohm resistor in series and add it to your wiring to the lamp. Should be fine that way.
Will do.

So to you it sounds certain that there's an issue here?

I don't want to do this just to find out that it wasn't the issue.
 
  #15  
Old 01-12-2019, 02:23 PM
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take a look at the OEM cluster and look for resistors if this one in the color bands are there, then it proves you need it but if you just did the straight wiring to your new charge light and didn't add the needed resistor then this problem happened, so with what you have said the alternator isnt being excited if your at 11 and 10V with you turning on acessories. Resistors will be cheap. you may be able to harvest it off your old cluster.


 

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