SI battery help

[e30construction]

Ok so my tach and economy guage arent working as well as my on board computer and from what ive gathered from searching is my si batteries may be dead so im in need of switching them but know nothing of this procedure and honestly know nothing about sodering stuff..So my first question wld be where could i take it to have it done or is there anybody in the mississippi area or nearby that would be willing to help if i paid them..second question is shld i just buy a known working cluster?

My speedo works as well as the gas light but the needle sways, heat guage works 2..just not the tach and econmy with the onboard computer..

Any help would be greatly appreciated

[dnguyen1963]

Gregs///M on this forum or bring the board to Batteries Plus.

[e30construction]

where is batteries plus is this just one location or is there one in the mississippi area? nvm searched the closest one to me is almost a 2 hour drive..so they will switch out the batteries for me?

[dnguyen1963]

I had them put in 2 NiCd batteries for a total cost of $10. However, if you send them to Gregs///M, he can also check the overall status of your board...not sure how much he charges. Contact him directly.

[e30construction]

I had them put in 2 NiCd batteries for a total cost of $10. However, if you send them to Gregs///M, he can also check the overall status of your board...not sure how much he charges. Contact him directly.

Probably shldve went this route but instead i went ahead and bought a known working one from a guy on the forum so hopefully all goes well and he's true to his word about it working

[e30construction]

other quick ?..if i replace the cluster and everything works and the bats are good will this make my on board computer work as well?

[Freude am Fahren]

if your OBC is also suffering I would check your fuses first. It's most likely not a bad SI battery (since the SI batteries don't govern OBC operation). If all your fuses are intact then check the ground connection next to your steering column by removing the panel over the pedals. If none of that helps, replace the entire cluster as the board is bad. I had the same exact problem. Good luck.

[e30construction]

cld you be a little more specific about the ground wire? ima look real quick but i was under there earlier and didnt see anything and to be honest the po made a horrible mess under the dash..i see a couple things that look unplugged like theres 3 square things one red one blue and one white that are just hanging there...theres several brown wires in a bundle that look to be cut and several little white plugs that are just hanging there but when i look i cant find anything that they wld plug into so idk and ive changed every fuse in the fuse box lol

[e30construction]

most of the lights work on the cluster but the indicator strip stays on yellow for some reason and ive read if the board is working properly the leds for that wld come on in key position 2 but they dont it just stays yellow..i pulled the cluster out to check all the connections and all look to be good

[e30construction]

just a quick look at what im working with




red blue and white square things

Brown wires that look cut

[lowsodium]

I had a bunch of wires under my dash that were cut, sliced, etc. Most of them were aftermarket cruise control which the previous owner removed. I just traced them back and removed them. Those brown wires dont look stock, but Im not sure.

[e30construction]

yea its a terrible mess and i know nothing about wires/electrics on a car so itll probly end up staying like that for some time..ive tried to find spots for the stuff but no luck..any clue on what the red blue and white square things are?

[lowsodium]

yea its a terrible mess and i know nothing about wires/electrics on a car so itll probly end up staying like that for some time..ive tried to find spots for the stuff but no luck..any clue on what the red blue and white square things are?

Im a noobie when it comes to electronics too.

I have issues with my gauge cluster too. Bouncing temp gauge and the right side lights are out, including the light on the clock. So far I replaced all the bulbs on the cluster and tightened the ground screw on the back of the gauge cluster. Didnt help much.

My next plan is to check the SI board for corrosion and replace if needed.

Its annoying because its really the only electrical issue i havent fixed yet.

Not sure what those plugs are. I think theres a wiring diagram on here somewhere. At least you track down the wires by color. Those plugs look stock, but I will snap a pic of mine when i get home.

[e30construction]

ok and where is this ground wire? ive bought a new cluster from a guy on here yesterday and he said hed ship out today so im waiting for hes reply with the confirmation and tracking code..but if mine can still work w.o switching them out by just a ground wire then i might wanna look into it and have an extra..my temp gauge is solid but i do have a bouncing gas needle..i get gas when the light comes on lol