Heating control stopped working after swapping climate control computer

[EdNL]

In my father's 530i (M30), 1988, with climate control and airconditioning, the heating control stopped working.

Because of a malfunctioning blower motor, even after replacing 2 swords (of which we didn't know 100% for sure whether or not they worked), we decided to swap the climate control computer.

After we did that, also the heating control stopped working. Heating was constantly turned on to the max.

We put back the old computer, but the heating kept on going. We already found a way to control the water valves manually, but it would be nice if we could get the climate control running again.

Any idea what might have went wrong when we replaced the computer with one from a 1989 735i? It looked exactly the same but had different numbers on it.

thanks!

[Javier]

Javier

[EdNL]

Yes, all fuses are fine. Thanks. The water valves also get their 12V supply. The valves also work fine when manually giving them ground and 12V.

[Javier]

from the valves to the computer are 12V (or check you can shoot close the valves grounding the wires at the connector to the computer.

Guess it is a 535i late 88, so they are pins 21 and 23 (yellow/brown and yellow/violet wires) onto the X610 (26 pin white connector, see picture).

Remember dial should not be at maximum heat to have voltage to the valves.

Javier

[Bill R.]

to recheck the connection on the climate control computer and disconnect the battery to reset the settings and see if it still acts up.



In my father's 530i (M30), 1988, with climate control and airconditioning, the heating control stopped working.

Because of a malfunctioning blower motor, even after replacing 2 swords (of which we didn't know 100% for sure whether or not they worked), we decided to swap the climate control computer.

After we did that, also the heating control stopped working. Heating was constantly turned on to the max.

We put back the old computer, but the heating kept on going. We already found a way to control the water valves manually, but it would be nice if we could get the climate control running again.

Any idea what might have went wrong when we replaced the computer with one from a 1989 735i? It looked exactly the same but had different numbers on it.

thanks!