Hi temp light on?

[Ninjakitty]

Hi y'all, so I just changed out the bulbs in the back of my dash cluster with green LEDs. Now, when I turn on the ignition, this is kind of lit up. A couple lights pop on and off real quick and are much brighter. Any thoughts on why this is happening?

I'll take some pics when it's darker outside

[Johnny Mullet]

If the dash illumination bulb is close to the warning bulb, the brighter LED might be bleeding through showing an outline of the temp light? Does it look like this with the marker lamps off?

[Ninjakitty]

Here is some new get shots. One with flash, one without.

[Ninjakitty]

As I understand it from some Google Fu, the light should light up when the ignition is switched on or motor started to show that the bulb works. Maybe it's showing that the temp gauge itself is broken? I'll have to track that down.

The bottom row of lights was previously covered and the top three from right were also covered. This bus's electronics has been chopped here and there from it's long camp bus life so who knows. I'm not sure if any of the warning systems actually work lol.

[Ninjakitty]

It is possible I removed the blower switch/relay for the extra radiator fan (excuse my layman's terms). However, I might not if either. I dunno. I do have the fan wires to manual switch at this point

[Ninjakitty]

This thing here looks familiar. Guess I need to trace some wires?

[Iceni John]

I had something similar when I replaced all my warning lights' incandescent lamps with LEDs. The warning light for the Jake Brake would then faintly illuminate even when the Jake wasn't working; it shone brightly when the Jake was on, but I don't like to see false indications all the time. I think it was something to do with LEDs' much lower current draw - the Jake light is powered directly from the ECM, so who knows if the ECM was being fooled by the LED.

This was one of several reasons I've now gone back to using good ol' incandescent lamps for all my gauges (except those with their own internal illumination such as Speedhut) and all my indicator lights. It just annoyed me to see TARD in bright blue whenever I had the RETARDER (the Jake Brake) on . . .

John

[cadillackid]

Some of the light circuits use the bulb as part odf the circuit.. an LED is still a Diode which is an electronic component that blocks power going one way.. its possible the circuits are designed that the resistance of the bulb played into the ciruit..



it also may be as others mentioned that the illuminator around the gauge is showing through... I wouldnt think you changed your temp warning light to a green LED??

[jazty]

yeah, if it's acting strange then try going back to a known working incandescent bulb.

On my '97 international I changed the Wait To Start bulb to an LED. Now it throws a code because the computer assumes the bulb is dead

[jazty]

For my case I'm going to try a resistor to see if I can satisfy the computer. I really like how bright the WTS LED light is

[cadillackid]

Navistar sends a pull-up voltage at the bulb,the LED only passes current one way and so the computer sees it as an Open circuit.. a resistor might make your bulb dimmer depending on how that LED module handles the lower voltage .. if they used a Zener inside of it then you have a good shot at it staying bright, otherwise it may make it dim.. worth a shot...

[Ninjakitty]

This is the back of the unit with the emergency lights. I'll try to find one of the old bulbs and switch it out.

Yeah, I changed em all to green. I figure it doesn't matter what color it lights up, if it lights up then something is wrong. This could just me being foolish though.

[jazty]

Originally Posted by Ninjakitty

I figure it doesn't matter what color it lights up, if it lights up then something is wrong.

As was anecdotally mentioned, it may matter. Maybe there is intentionally always a tiny bit of current flowing which isn't enough to properly illuminate an incandescent bulb, but is enough for an LED. LEDs have very different characteristics when compared with incandescent bulbs. It's worth testing the lights themselves before assuming other systems are failing.