SI board issues?

[Philipangoo]

I bought a M50 swapped cabrio last week site unseen so I honestly don’t know too much about the history of it.

All the gauges on the cluster work EXCEPT the tachometer. The PO also had shift lights installed by innovative goods. That and the mpg gauge don’t work since they are tied in with the tach.

in addition to this I don’t get any si board lights on start up. Not does anything besides battery light up on the bottom row. (Check panel has like 4 things lit up)

I pulled the SI board and to my surprise the cluster was refurbished by BavRestorations in 2016. I tested voltage on the 2 batteries which were the late model AA size ones and got 1.25 volts on both of them which is right in line with what it should be. I took pics of the board and nothing stands out to me as bad or out of place. No visible burns or shorts that I can tell. I’ll upload them from my phone as a reply.

i did swap fuses 10, 12, 21 since I had a bunch of 7.5 on hand.

im about to bite the bullet and mail the cluster back to bavrestore because I just can’t figure this out. Any ideas ?

i get no lights from cluster in key position 1, when I start the car I get a faint glow in inspection light, and I see the tach needle move up and back down, but it quickly goes away.

The PO had a bad car battery in there before and told me he jumped it a few times to drive. When I purchased the car I brought a new battery.

[Northern]

Is the jumper pin on the SI board in the correct position?

[Philipangoo]

Is there somewhere I can find a Pin map of the SI board ? I’m not really sure which one is jumper pin.

[Philipangoo]

I made this post on the r3v fbook post after doing some more testing on the car.

Trying to chase down some electronics issues.

When I start the car my cluster lights up properly like it should and by ac/blower motor blows. Once the car is started these functions immediately go away. Like literally after ignition sequence is done it’s all gone. No blower at any speed no lights on the ac buttons, no SI lights and maybe unrelated but no Tach function / mpg function. Speedo still works and when I turn on headlights the cluster is back lit. Just no service leds.

I checked battery and and voltage while running seems that both batt and alternator are fine.

I have checked related fuses to both functions and swapped them out with new fuses.

I pulled SI board and tested its batteries, I have late model double AA size set up both batteries show 1.25v.

Could this be a relay issue ?

91 Cabrio that was M50 swapped by PO. I received it this past week.

Any ideas on where I should check next ?

[Vincenze]

Shouldn't the service lights turn off when the engine is started?

[Northern]

Is there somewhere I can find a Pin map of the SI board ? I’m not really sure which one is jumper pin.

I looked at some NiCad SI board pictures and I can't actually see if it even has one. If you find pictures of the Lithium battery boards, they often have an orange sticker that points to the jumper that needs to be switched before the SI board works.

A lot of those issues don't really sound SI related? maybe something with the unloader relay?

[Philipangoo]

I thought it was a Relay problem too, I swapped unloader K7 with my Lowbeam K4 relay (they were identical) and started the car up. Still got same issue. I will prob need to do some voltage, continuity, and resistance tests. I’m a electronics noob so this gonna suck.