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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.
Awesome. Thanks. You think this will solve the engine light as well?
It wasn't on before I did this project.
Also, I'll order one up because after running the new set up for a while to make sure I'm not gonna have any issues I'm probably going to sell it.
Are you using LEDs in the batt and check engine indicators?
Others have tried LEDs in our era trucks and had issues of the LED's lighting up as they require MUCH less current to light up than the incandescent lamps.
I know on the low batt/charge indicator ,a LED will not function properly even with that 520ohm resistor in place, It will stay lite up, but a old bulb which takes alot more current to light up will work. I heard of a fix but don't remember what it was.
As the others have said, please verify at the battery with a meter, with engine running you should get 13.6v to 14.6 volts. Anything less means its not charging the battery.
If possable and as a good test, replace the LEDs with bulbs and see what happens.
Also that cluster looks good! In near future, I'll redesign my cluster, but go digital display.
I am using an LED on my check engine light, didn't seem to have any issues my charge indicator has a stock bulb in it tho as this issue i knew about before swapping bulbs.
Now with him not having that 510ohm resistor there obviously wouldn't allow the the proper resistance to be letting that circuit excite the field for the alternator, now the LED bulb is an ultra low resistance so maybe the issue is there on top of needing the 510 ohms you'd need the resistance of the 194 incandescent bulb (194 bulb should draw 0.27A and Volts X amps= 3.8W. So maybe adding another resistor in series equal to 4W could be it? Another thing I can see is a LED is not a bidirectional polarity item so this could be an issue, maybe he could try and add back that resistor (510) and try using a regular type bulb and see if the light goes out. I guess worst case scenario without re engineering the charge circuit he could just run an indicator with a regular bulb if it works.
Using the numbers MPP8405 posted for a 194 light bulb, resistance would be ~52 ohms through the light bulb. Combine that with the 510 ohm resistor in parallel and the equivalent circuit resistance would be ~47 ohms. If the LED is near zero resistance, it will take a larger resistor in parallel to get to the equivalent circuit resistance. Since you are making the whole thing, it might be easier to wire a resistor in series with the LED charge bulb to get the required resistance. The fused circuit is 20A, so I would size the resistor accordingly.
The check engine light sounds like it operates opposite normal - on when it should be off, and off when it should be on. Is it powered by switched 12v and grounded through the check engine circuit in the computer?
Using the numbers MPP8405 posted for a 194 light bulb, resistance would be ~52 ohms through the light bulb. Combine that with the 510 ohm resistor in parallel and the equivalent circuit resistance would be ~47 ohms. If the LED is near zero resistance, it will take a larger resistor in parallel to get to the equivalent circuit resistance. Since you are making the whole thing, it might be easier to wire a resistor in series with the LED charge bulb to get the required resistance. The fused circuit is 20A, so I would size the resistor accordingly.
The check engine light sounds like it operates opposite normal - on when it should be off, and off when it should be on. Is it powered by switched 12v and grounded through the check engine circuit in the computer?
Yes, I was going to find some resistors and get them ordered up today if I can decide on which ones I need. I was just going to be looking for the 510 ohm plus the watt from the original bulb.
I could have have sworn when I ordered these lights that the company said they had built in resistors so I'm going to have to find out what those are and subtract that. This sucks.
No, going 3G alternator still requires the energizer wire and lamp/resistor setup. It is not self exciting. Going 3G alternator gets rid of the fire hazard of the 2G's side plug. Also you can get a 130Amp version too.
You need to check to see if you are getting 12V on the LG/R wire going to the alternator with key on engine run. Also check the Y/W wire going to alternator, with key off/on it should have battery voltage on it.
No, going 3G alternator still requires the energizer wire and lamp/resistor setup. It is not self exciting. Going 3G alternator gets rid of the fire hazard of the 2G's side plug. Also you can get a 130Amp version too.
You need to check to see if you are getting 12V on the LG/R wire going to the alternator with key on engine run. Also check the Y/W wire going to alternator, with key off/on it should have battery voltage on it.
Thanks Eddiec. I'll look further into it tomorrow after work and get back to you. In the meantime I'll get a resistor ordered up. Thanks for all the help.
The engine light is ran to the Pink/Grey wire 658 Check Engine Input from EEC (Pin #9 from C251)
Not sure what's going on with that but it wasn't on before the project.
I would think between a quarter and a half should do just fine for the resistor.
510 ohm and I wouldn't think that tiny bulb is more than half a watt.
01-12-2019, 01:45 PM
