SFb16eg6

hey guys been lurking here for years but finally found a question that i could not find an answer to from searching.
a little background: i have a 93 with a b16a2 with bolt ons. im running s300 on p72, dx wiring harness with rywire vtec subharness. eventually going to be using this car for hpde events and auto-x

hopefully someone here can help...

my check engine light does not come on with ignition on anymore. (i am a smog technician and have a habit of making sure the MIL works every time i start a car)
one day it worked and one day it didnt basically.
ive replaced the bulb with known good bulbs so i know the bulb is not the problem. ive also shorted the diagnostic connector just to see if the MIL would illuminate and it didnt.
ive checked the wires on the plugs at the back of cluster and everything looks good.
ive checked all fuses and grounds and everything is good.

so the wierd part - now my cruise control light stays on at all times (i dont have cruise control). i can easily just remove the Cruise Control bulb but id still like to know why it is even illuminated in the first place, as this makes me think something is not hooked up properly..
first i thought i screwed something up and the cruise control was basically acting as the MIL however i have no codes through hondata s300..

my questions are: why the heck is cruise control illuminated? and what would cause the check engine light to randomly stop functioning?

any and all help is appreciated, thank you.

knoxrocks222

Karma?? Lol just messin with ya have you tried a different cluster?

fragmare

If you have a digital multimeter, you could start checking for voltage starting at the bulb socket and trace it back until you find the problem. also, check solder joints on the cluster itself. if they're cracked, even a little, reflow the solder.

SFb16eg6

Fragmare, are you talking about checking voltage and solder joints along the copper striped backing on the exterior of the cluster? Sorry I don't know the proper term for it..

fragmare

Yea, that almost paper thin sheet of plastic backing behind the cluster. I'm going to guess one or more of the solder joints finally gave up the ghost. I'd check those first. Hell, even if they look fine, reflow them anyway... take a soldering tool and touch it to each solder joint just long enough to re-melt the solder. Sometimes you may need to add just a tiny dab more solder, so have some rosin core small gauge handy. Careful to not hold it on there too long and get the plastic sheet hot enough to melt.

You can also take a multimeter and test for voltage along those copper strips. If the one leading to the CEL bulb isn't supplying voltage keep tracing it back and looking for voltage until you find it. If you find that there is no voltage at the main plug that supplies power to that particular bulb, you'll have to start tracing the problem further up the wire harness, because that means the problem isn't in the cluster.

Do the other cluster bulbs light up when they're supposed to? The cruise control bulb might be controlled by a different plug than the other bulbs (The green plug behind the cluster powers the cruise control stuff, iirc)

Anyway, check the solder joints first. That'll be the most likely culprit and easiest to find and fix.

mreddy

My friend had a problem like that. He cleared gauge board with 'contact lens cleaner' and solved.

SFb16eg6

So I tried the alcohol, and reflowed the solder points and still no check engine light. I'm going to try to find a cluster to borrow and see what happens. Thank you all for the suggestions.