CHECK Indicator problem

[Martin323i]

Hi there,

Before I changed the engine in my car, the brake LED and check light (flashing) would go out when the brake pedal was depressed. After swap the brake LED on panel above rear view mirror goes out, but check light keeps flashing, until check button is pressed.

This isn't major, but it is mildly irritating. Why is this happening? What can I do to correct it?

[Brianmoooore]

Came across one like this once. Turned out to be nothing to do with the brake lights.
One of the other LEDs for something non important was faulty and not lighting, although the sensor in question had tripped. This kept the check light flashing after the brake pedal had been pressed.

[Martin323i]

So then I should test all sensors and see whether the corresponding LED lights up when 'faulty'?

[Brianmoooore]

That, or swap in a different check panel, which is how I discovered what the problem was.

[massive]

What if the dash check light stays on (not flashing just on all the time?) when no lights are lit on the above check panel.

[Brianmoooore]

What if the dash check light stays on (not flashing just on all the time?) when no lights are lit on the above check panel.

Should think that can only be a faulty check control panel.

[Martin323i]

That, or swap in a different check panel, which is how I discovered what the problem was.

OK, thanks Brian.

[massive]

What if the dash check light stays on (not flashing just on all the time?) when no lights are lit on the above check panel.

Should think that can only be a faulty check control panel.

Cheers Brian, is there anything you dont know about?

[Martin323i]

Well, ended up being the engine oil level sensor/switch. When I took the connector's rubber boot off two of the wires were not connected.

Brian do you know which wire goes where? The connector is numbered 1,2,3.

There's a yellow, a brown or red (was a bit dark down there), and a blue.

[Brianmoooore]

Well, ended up being the engine oil level sensor/switch. When I took the connector's rubber boot off two of the wires were not connected.

Brian do you know which wire goes where? The connector is numbered 1,2,3.

There's a yellow, a brown or red (was a bit dark down there), and a blue.

I've got a circuit diagram in front of me, but the wires change colour as they go from the check control panel to the sender.
Sender 3 = brown = earth
Sender 2 - blue/white - blue - purple/green - check panel pin 20.
Sender 1 -blue/purple - green/yellow - blue/black - check panel pin 16.

On the sender unit pins 2-3 should be about 1000 ohms when full of oil and open circuit when empty.
Pins 1-3 should be short circuit (0 ohms) when full and open circuit when empty.

[Martin323i]

Thanks Brian,

The colours dont quite match mine, but I'll undo the boot on the panel-side of the connector and see if those wires match up. Otherwise I'll just test for continuity between the different wires. That should tell me what wire goes where, assuming the switch isn't broken.

[Brianmoooore]

If you get the earth right, then there's only two ways to connect the other two. One way should work properly, and the other will turn the low level light on, unless the level IS low, when it will turn off.

[Martin323i]

Right, I opened up the check panel and found the engine oil level LED broken out (I'm pretty sure someone was there before me and screwed it up)

With a bit of help from my brother it's fixed now, so the led keeps lit all the time.

I took the wires from the panel side of the connectors and connected the green/yellow (static switch) with the red(earth) to comlete the circuit and left thew blue (dynamic switch) loose (open circuit). According to the bentley this is how it should be when oil level is correct. The light was still on.

Brian, I see in your post all circuits should be closed, so maybe the bentley is wrong. I'll connect all the wires together tomorrow and see if this works.

[Brianmoooore]

Brian, I see in your post all circuits should be closed, so maybe the bentley is wrong. I'll connect all the wires together tomorrow and see if this works.

That's because I posted it wrong!!
Try this:
pins 2-3 should be 1000 ohms when full, short circuit when empty
pins 1-3 should be short circuit when full and open circuit when empty!

[Martin323i]

OK, no probs. Will see what I can do later today.

Cheers