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JScritch
04-19-2006, 04:59 AM
Ok, I've read the owner's manual and I'm still not getting it. What exactly does the A/M switch next to the gear selector do?

When I put the car in "D" the dash displays "ED" and when I put the car in "3" the dash displays "S3" but nothing happens in either setting with I try to use the A/M switch.

Is the dash display supposed to change depending on whether I select A or M?

Is the A/M switch supposed to light up when I select one or the other?

Is it possible I have a faulty switch that could be causing some of my "trans program" errors?

I pulled switch and sprayed it real well with contact cleaner since it had a lot of gunk on the outside of it, but maybe it's still bad.

Rus
04-19-2006, 05:03 AM
The dash display should show an M in place of E or S when you slide the switch to the M position. The switch may be faulty. You can check by swapping it with your sunroof switch. They are essentially the same switch and can be safely interchanged for testing. Hope this helps.

SchnellE34
04-19-2006, 05:22 AM
Ok, I've read the owner's manual and I'm still not getting it. What exactly does the A/M switch next to the gear selector do?

When I put the car in "D" the dash displays "ED" and when I put the car in "3" the dash displays "S3" but nothing happens in either setting with I try to use the A/M switch.

Is the dash display supposed to change depending on whether I select A or M?

Is the A/M switch supposed to light up when I select one or the other?

Is it possible I have a faulty switch that could be causing some of my "trans program" errors?

I pulled switch and sprayed it real well with contact cleaner since it had a lot of gunk on the outside of it, but maybe it's still bad.
First of all, I would suggest allowing us to know what year and model you drive. Second, the A/M switch means Automatic and Manual modes.

While in Automatic mode: The E you see on the dash means Economy. The most economical way to drive the car. When you switch out of Drive and into the numbered gears the S means Sport mode.

While in Manual mode: The M on the dash means Manual. Basically when you move into a lower gear, the trans willl stay in that gear until manually shifted out.

I agree JScritch, you should flip flop the sun roof switch to troubleshoot the 'trans program' error. Otherwise, do a search on the board for that error. Searching is the best way to find quick answers

JScritch
04-19-2006, 05:26 AM
Sorry, I usually post the vehicle information at the top of my posts and completely forgot.

I have a '92 525i auto with 98,000 miles.

JScritch
04-20-2006, 09:41 AM
Here's what happens no matter whether I click the switch to "A" or "M"

D = ED (on dash)
3 = S3 (on dash)
2 = S2 (on dash)
1 = S1 (on dash)

This was with both switches installed (normal one and the sunroof one). So, how do you tell if the switch is actually working.....do I have to take it for a drive and see whether it shifts on it's own?

Just one other observation is that the switch moves back to center after pushing towards A or M. Is it supposed to stay towards one side or return to center like it does?

I did pull the switch apart and it was so gunked up and gross inside that even after a good scrubbing it still looks a little dirty. But, I don't want to spend $$ on a new one if I don't have to.

JonE
04-20-2006, 11:51 AM
I never use the "M" position on my car, only to initially test it out when I bought it. Supposedly this is used to lock the gear into say, #3, so that you can pull away in snowy/icy conditions without losing control. I live in a snow area and have never, ever felt the need to use the "M" position. If my switch ever malfunctioned, it would have to be very cheap for me to get it fixed. As long as it still worked in the "A" (normal) position, I probably wouldn't consider fixing it. Just my opinion.

Javier
04-20-2006, 01:00 PM
switch connector and briefly connect the Brown/White wire to ground (Manual request) and the Brown/Red wire to ground (back to Auto request). The Brown/Orange wire of the same harness should be connected to ground. By the way, does your switch light illuminates when lights On? If not Brown/Orange may be floating and not grounded, leaving the switch inoperative.

Javier

Robert K
04-20-2006, 05:45 PM
When you put the switch in "M", this puts the tranny into manual mode. In other words, it's just like driving a manual tranny car. If you leave it in "3", the car will stay in 3rd gear until you choose another gear. So, if you leave it in "3" and come to a stoplight, you will pull away in third gear. You can also shift manually with the car in "A" mode. The difference though is that when you come to a stop, it will downshift into first. Then when you take off, it will shift up to third gear, but not past third gear. In "M" mode, the tranny will hold the chosen gear indefinitely until you move the lever to the next position up or down. Does that explanation help???

Grace and peace,

Robert K
1991 535i