Battery Drain issue. Coming from cluster.

[markpopaj]

Hi All,

I have a e30 vert m30swap.

Ive searched and searched but the closest thing to my situation, the guy ended up not having a answer to the problem.

I have a significant battery drain, but it disappears when I unplug the blue plug behind the cluster. I went through all the pin holes and one of them is still live even when the car is off.
** its the second pin from the bottom( wire loom facing down)**


Anyone has an idea on what this is? and if it is intended to consistently give power?

[earthwormjim]

Check the batteries in the service interval board in the cluster.

[markpopaj]

Okay Thank you,
Let me check it out.

[earthwormjim]

I meant cluster by the way, not odometer.

[Gregs///M]

Definitely the SI board. What happens is the batteries drain very low, causing the SI board to turn on and off as it enters the regime fully drained. When the SI board switches on and off, it causes the 30+ transistors to switch on and off too, and considering their age being 30 years old, they will get stuck in the open or closed state. Some of these transistors are responsible for powered or triggering the SI leds and the oil /inspection lights. They can be switch on partially or fully and sometimes the light from the indicators can be bright or so dim you cannot see with naked eye.

So that is where your drain is coming from, I have seen it hundreds of time. Easy fix is to remove the LED panel from the SI board, remove the Si board but tach, temp, MPG, OBC and SI lights wont work or have it refurbished by us, we specialize in the SI board repair.

Hope that helps.