Locobob's Interior Mod Thread

[Locobob]

I'm thinking it's got to be a ground issue of some kind since the dic warning lights are always powered and turn on through grounding.

[GOLDCYLON]

Originally Posted by Locobob

Couple of shots of the DIC, the plug-in for the TPMS unit just slightly obscures the service ride control light in the upper right hand corner but that's not going to hurt anything.




With the cover removed. Something odd is going on with the check engine and service abs bulbs. They both come on full bright as they should at initial key on... but then they stay on at a reduced brightness. You can see the service select ride at the far left on full bright (need to try to reset this), then the check engine light is at about half brightness, and the service ABS is just barely emitting a glow. All of these should be off. Any idea what could be causing this??? The bulbs are all LED's. I really perplexed, I don't see any obvious wiring issues.

Id suggest putting the bulbs back in to see if the condition is the same. The Leds might be the problem. Unless they (the LEDs) have individual resisters the old school DIC might be having a problem with the voltage. D

[Locobob]

Originally Posted by GOLDCYLON

Id suggest putting the bulbs back in to see if the condition is the same. The Leds might be the problem. Unless they (the LEDs) have individual resisters the old school DIC might be having a problem with the voltage. D

I tried bench testing the unit with a 9v battery and some wires, everything lit as it should and I didn't see any signs of crosstalk between the circuits. The SES and Service ABS run side by side on the flexible circuit board and terminate directly across from each other so I thought maybe something was bridging them but couldn't find any sign of that, hmmm. I'll try removing and swapping some bulbs out in a bit.

[Locobob]

Did some testing: pulling the SRC bulb changed nothing, switching the SRC to the stock bulb changed nothing. Pulling either one of the dim LED's did not effect the other one. Now what did work was replacing the dim LED's with stock bulbs, the lights went out instead of being dim, and they did function normally during the key on bulb test. Not sure what to make of that...

[GOLDCYLON]

Originally Posted by Locobob

Did some testing: pulling the SRC bulb changed nothing, switching the SRC to the stock bulb changed nothing. Pulling either one of the dim LED's did not effect the other one. Now what did work was replacing the dim LED's with stock bulbs, the lights went out instead of being dim, and they did function normally during the key on bulb test. Not sure what to make of that...

Who's the man lol

[Locobob]

Originally Posted by GOLDCYLON

Who's the man lol

If you can explain why that happened I will gladly say you're the man. The warning lights have constant power and turn on by being grounded...

[GOLDCYLON]

Originally Posted by Locobob

If you can explain why that happened I will gladly say you're the man. The warning lights have constant power and turn on by being grounded...

I have no idea but have a lot of experience on LEDs performance.

[Locobob]

Originally Posted by GOLDCYLON

I have no idea but have a lot of experience on LEDs performance.

I was just talking to Scott Fabre about this and he thinks it's likely that there is "leakage" at the grounds on those two systems. The very low current requirements of the LED's would explain why they light up when incandescents do not such being the case.

[GOLDCYLON]

Originally Posted by Locobob

I was just talking to Scott Fabre about this and he thinks it's likely that there is "leakage" at the grounds on those two systems. The very low current requirements of the LED's would explain why they light up when incandescents do not such being the case.

This is a plausible arugment. Back in the day when LEDs were becoming cheaper and usable in cars a mere 8 years ago you used to have to wire in resisters in order for them to operate properly. Taillight leds problems were resolved with replacing the mechinal flashing units with a electronic flashers that could handle the microspeed of the LEDs and allow them to "flash" or "pulse" if you prefer correctly. When you search online these days for replacement LEDs for your car for normal LEDs and SMDs you will see now the catch phrase "no error". These are the type that have the resisters built into the units. As the cars get smarter and intergrate in other vehicles DICs the earlier replacelent LEDs which show or "Display" an error code or the bulb as being out. Adding the resisters to these units solved that. So this being said if you can find a replacement SMD that will fit that is a "No error" type this might work.

Back to your example if the ground is not a true ground even a small amount of "Stray" voltage will allow an extremely low to power already SMD or LED to glow dimly. It really would not take a lot of milli amps for that to occur. Hence your problem. It makes complete sense.

[Locobob]

These are the LED's I used: http://www.ebay.com/itm/4pack-PC74-T...243f65&vxp=mtr
Not sure if there is another type that would alleviate the issue or perhaps a way to modify the circuit to prevent the low current glow... I may just be stuck using the stock incandescent bulbs in these two locations, which is kind of a bummer as the LED's look really sharp, but then again they are just warning lights which I wont be looking at all the time.... hopefully lol