Well, I bought this Civic Si, its a mess. its a 89 (long story)

But it has an 90/91 cluster in it.

Long story short, I've got the gauge to work 99%. Everything but the oil pressure light.

Can anyone tell me what voltage the wire puts out? Or if it is a ground?

Or what voltage it will put out with the ignition on, but the engine off?

Basically I have two yel/red wires left over, one seems to put out no voltage, the other puts out .45v. (regardless if the oil pressure wire is hooked to the switch, engine running, or just ignition on w/o engine running)

I would normally just leave it and move on, but im going to sell this car and I want it to function the best it can.

if anyone has a decent way to trouble shoot it im all ears.

PS. ive looked at over 8 pin out diagrams and if it was not for them the gauge would still be black at night!! but they didnt help me figure out why i had 3 yel/red wires. lol


thanks,

Dan

 

Sorry I have no info on an 89 CRX, but from what I do have it indicates that the oil pressure switch supplies a ground to the warning light when pressure drops too low, it has to be a ground as the oil pressure switch has only one lead running from it,

You have tried just grounding the oil pressure switch lead to see if light comes on, right? 94

"Idiot lights are pretty simple, 12V+ on one side and a switch supplies a ground, either when switch is "on" or "off" depending on what the switch is for, EG; an oil pressure switch supplies the ground when when pressure is low, the pressure keeps the switch off, the brake fluid level switch is off until level drops too low turning switch on and illuminating the hand brake light, the hand brake switch itself is off until hand brake is pulled, turning light on.
I am pretty sure your oil light should have 12V+ on one side and the oil pressure switch supplies a ground to it, if you test the lead running from the pressure switch to the light when disconnected from the pressure switch, [or when switch is not supplying a ground because there is oil pressure] the lead will test as a power lead @ 12V+ or less, depending on resistance of bulb filament.

 

thank you for the reply.


i bought an 89 civic with a 91 ecu and 91 gauge cluster...

long story short i had to repin all the connectors inthe cluster...

i had 3 yel/red wires, everyone else just has two... i duno why but this car is very special... LOL

the wire original wire i had plumbed into the oil pressure light was correct.

the crazy thing is, the extra yel/red wire i had was for the seatbelt reminder! (i found this out by swapping it into the oil pressure slot and the friggin oil pressure light flashed with the warning beep from the cluster!! lol)

so i swapped the other yel/red (oil pressure) into the 90-91 oil pressure location, put the seatbelt warning into the 90-91 seatbelt warning location, and BAM! they both worked.

i guess they need each other to work correctly.

i am so happy. lol