groverwood

I recently replaced my cluster on my '93 SC400 because of burnt out needles. After installing the replacement cluster, the speedometer and tach and all lights do not work.

I swapped out the new with the old, thinking i may have a bad cluster again and i still have the same problem. No Tachometer and no speedometer. Also no lights. all the other bulbs light. the oil light, the track, airbag,etc...

what did i do? is seems like i blew a fuse or something, but i checked all the fuses under the drivers side dash and under the hood.

please help. i'm desperate as this is my daily driver. I'd hate to have to drive my '91 Cutlass around .

gamimnon

there are specific broken electrical connections to the odometere, which then goes to the custer for the spedometer. with all the lights on like that seems like a blown alt fuse. id check those 2 things. take apart the odometer and check to see if the soldered connects to the plug to the odometer are still there. 2nd id check the alt fuse in the engine bay.

WadeLovell

iTrader: (5)

I agree it sounds like you blew a fuse. If you have to, you can drive without the cluster. OTOH, if you have an Olds, drive it because if you start the SC without the cluster installed you will have to reset the airbag warning light which I have found to be a PITA.

Biggu

iTrader: (12)

check your ground for the gauge cluster. if the grounds are off then they will not work. ask me how i know.

groverwood

what do you mean? where is such ground?

Biggu

iTrader: (12)

center console is where mine was but I moved it since I redid alot of my wiring.

groverwood

OK, now I'm thoroughly confused. There is a ground wire in the center console that connects to the instrument cluster?

the strange thing is, it worked fine before i got my clumsy hands on it. Is this ground something that I may have broken while doing the cluster swap?


secondly,



i checked the alt sense fuse (15A) and it was fine. there is, however an ALT relay thing. how can i tell if that is bad?

gamimnon

there are two major fuses that are associated with the alt. an (clear if and you cannot take it out red case i think) 140amp i think and the 15amp for the alt. the major fuse would blow if you somehow grounded out the whole system. iv seen it go from switching battery terminals, grounding out the wire from the alternator to the frame say by wrench (lol always disconnect the battery) ect. takes a big mistake alot of sparks. if your wondering if its the relay just check to see if it clicks, or get a new relay. im not sure what ampage youd need though.

groverwood

the 15 is good and the 140 relay is good too, (i think) it looks clean and fully intact. I made no mistakes when installing the cluster other than some minor damage to one of the connector tabs. all the wires are intact and connected.

the strangeness is in the fact that the old cluster (burnt out needles) is doing the same thing. this tells me that the issue is in the wiring somewhere. Is there any in-line fuses or grounds I can check?

i'm starting to bedate having a professional figure it out if i could find somebody with know-how and time to help.

gamimnon

what i would do now is to use a multi meter to check to make sure that the cluster signal is going out to the ecu. or visa versa. thats how id find the specific problem in the cluster testin each wire to the obo.

DrtSwinger

I'm in the same boat as you groverwood. My gauge cluster had burnt out needles and random backlight bulbs out, but other than that it worked great. Then one night the whole unit went out, except for open door, airbag, and the clock. No gauge readings or backilight at all except for the clock, which will still dim up and down correctly using the switch.
So I sent the unit off for repair, and he was able to get my cluster to work in the exact condition before the major short-out. So I figure I might have a ground issue as well, since I got the cluster back today and had no luck with it working. I'll let you know if I have any luck checking grounds....

groverwood

i figured it out. when i was replacing bulbs from old cluster to new, i didn't put all the screws into the board of the cluster. I wanted to make sure it worked before i tightened all 20 screws. well, turns out, i'm an idiot. the screws on the board are actually ground screws and by not having them all secured, the gauges did not work and it also caused a ground short which burnt out all the bulbs. yup. all the main backlight bulbs were dead. I did some pick and choose between the two clusters and have enough in there now so the tach and speedo work and i can see it all.

I still would like to replace all the bulbs with some clear, bright ones, but for now, I'll take it.

another note: excuse me if i sound ignorant, but I didn't pay too close attention to my actual mileage. i usually have it set to tripA so i can gauge my actual gas mileage. (i get about 22mpg) anyway, i think the mileage display on the new cluster is different than the original. so, that would mean the mileage is stored in the cluster, not somewhere else in the car. is that the case? I thought my car was well under 200k and now it read 220.

bodydrager

iTrader: (4)

The mileage is stored in the cluster and not the ECU like new cars.

gamimnon

lol yeah, having all the screws on the board are important. the milage is stored in the cluster as bodydragger said. as far as i know there is no way to make it go up on milage without the speedo and ecu processing to it.

groverwood

I am slowly rebuilding my cluster with new needles that I have from another and want to put in new bright bulbs in the thing. Where can i find the right ones for the right price. 93 sc400.