Skip to main content ↑ ↓
Topic: Mystery Switches inside dash (Read 928 times) previous topic - next topic

Mystery Switches inside dash

Inside dash area.  Driver left below A pillar is a  black plate mounted with 2 switches. One momentary and one on/off. These are in dash area covered by dash. What are they for.

Re: Mystery Switches inside dash

Reply #1 –
If I remember correctly they are used to activate the flash codes for the engine ecm and the abs controller. I thought the hey were both momentary switches?
When activated they will flash fault codes out the respective abs warning and check engine lights in the instrument panel.

Steve

Re: Mystery Switches inside dash

Reply #2 –
Found this post.
Left side Rocker switch is engine diagnostics

To Retrieve Blink Code(s):

Ignition switch on and switch on to flash codes.

It will only read active codes.

No active codes it will not flash.

Right side is ABS codes
To Retrieve Blink Code(s):

Turn ignition key to the ON position.

Wait for three seconds prior to proceeding.

Apply and release the service brake pedal once.

Press and hold the momentary test button under dash panel for one to two seconds.

The indicator light will illuminate while test button is pressed.

After releasing test button, observe the ABS warning indicator lamp.

The lamp will turn off and the blink code will be displayed: 1-1 indicates no system faults.

Re: Mystery Switches inside dash

Reply #3 –
On my 1998 320. One is for the idle speed. each push of the momentary switch will increase or decrease idle by 25 RPM.

Re: Mystery Switches inside dash

Reply #4 –
One of mine are for the idle adjustment as Bigdog stated. 1999 U320

Re: Mystery Switches inside dash

Reply #5 –
Thanks all. After messing around under dash for day and a half and nearly ready to slash my wrists I came upon these switches. It confirmed my thinking that only some satanic sadistic s.o.b could conceive and design this mess and to top it off would hide switches out of reach and sight for grins and giggles. Of course upon my seeing them and even beginning to know what they were for, I started flipping them. Only after. thinking they could be some sort of kill switch or timed self destruct button that would only activate 250 miles from nearest tow or service facility. I now rest much easier and only half wonder what the hell was I thinking when I decided to undertake this adventure
 

Re: Mystery Switches inside dash

Reply #6 –
Be patient with yourself. The Most fun is yet to come.......