1998 540i exterior temperature gauge reads -40 - BMW Forum

236goinggolfing · 05-29-2008, 12:46 PM

Hi everyone I am new to this forum and have alot of questions about my 1998 540i. First is my exterior temperature gauge is reading -40. Does this have any affect on the ACS system and what should I do to fix the problem?

Thanks for any help ahead of time.

witeshark · 05-29-2008, 01:16 PM

It won't affect the A/C system. Almost certainly the outside sensor is damaged or missing.

winters97E39 · 05-30-2008, 03:25 PM

You don't happen to live at the South Pole do you?

236goinggolfing · 06-02-2008, 08:42 PM

Thanks guys no I just live in Pittsburgh, Pa. GO PENS!!

236goinggolfing · 06-02-2008, 08:48 PM

I also have a problem with the check brake lights warning come on every time I start the car even though the lights work fine. I heard that if you don't use BMW lights it sets this off but that is what a unreliable source told (non-BMW owner) me.

Bimmer M.D. · 06-07-2008, 11:41 PM

The temp sensor is disconnected. It is a common problem for both the E36 and E39, and not a difficult fix. Simply reconnect the sensor.

236goinggolfing · 06-09-2008, 11:30 AM

Hello again and thanks for all of the help. I have found the temp sensor and there were just exposed wires, looks light a bad park job and sensor got ripped off. Does anyone know of a junk yard close to Pittsburgh, PA were I can get a new connector.

The

236goinggolfing · 06-09-2008, 11:46 AM

The next issue with the car is that it shimmies at 45-50mph with light braking. I know the these cars have a control arm problem after 100,000 miles but does both front and rear need to be replaced and is this something that can be done at home or at a shop?

I am also replacing the DSP woofer box and replacing with two 8" Dual voice coil woofers. Has anyone done this and can I use the existing wiring?

I know more questions this guy must be an idiot!

Is there any way to reprogram the speedometer for different tire sizes?

My car has the "check coolant level" warnig light come on and the level is fine is this a sensor that needs to be replaced?

darkhorse737 · 06-09-2008, 08:11 PM

shimmy with light braking.... that's warped rotors. have 'em turned if they are still within the specified thickness; replace with stock; or, upgrade to cross-drilled rotors accordingly ;-)

i wouldn't look at control arm just now- thts going a bit too far for wheel shimmy :-)

My car has the "check coolant level" warnig light come on and the level is fine is this a sensor that needs to be replaced<<< sensors for coolant level-they're no different in principle than the floats u see in your water closet. chances are, it got dirty and is stuck at bottom, thus ur light. If yours is the kind that u can disconnect & unscrew from the coolant reservoir, by all means, take a chance and clean it ;-)

yes, you can have your speedo recalibrated. try and buzz me later on... am trying to remember the programs that allow you to do this...

236goinggolfing · 06-12-2008, 08:57 AM

Thanks for all of the help I was looking at some slotted-cross drilled rotors and found that my temp sensor was ripped off and need the connector for a new one. Now I am looking for a junk yard that has an e39 for a connector.

I also found my problem for the poor sound system! The rear deck bass unit was removed and now I am rigging up two 8" dual voice coil subwoofers in the back and only need help with wiring for the DSP rear deck bass unit.

Thanks guys I appreciate your help.

MyCali540i · 08-11-2008, 12:35 AM

Hey,

Just a heads up, I read on another forum that the warped rotors would cause the shimmy issues at any speed. It seems logical. Any comments?

Also, I had a shop check and my bushings are done. I need to replace them. Also found control arm bolts were not tightened to spec. He tightened them for me.

It helped a bit but the shimmy is still there and I here a metal to metal rattle when hitting bumps.

Frustrating!

AlpineSixAndSeven · 08-11-2008, 01:24 AM

^ what did you have replaced? i would do front control arms, thrust arms and check the Tie rods and draglink(inner tierods) and check the idler arm....

darkhorse737 · 08-11-2008, 08:47 AM

Just a heads up, I read on another forum that the warped rotors would cause the shimmy issues at any speed. It seems logical. Any comments?

<<<theoretically possible,yes... but the shimmy won't be felt unless u apply the brakes. Shimmy at any speed would be more of suspension/steering components going bad(rubber parts and tie rod ends especially); and also problems with wheel balance.

metal-to-metal rattle on the bumps is also a suspension/steering issue; but i will not discount the idea of loose brake parts either

236goinggolfing · 08-11-2008, 08:23 PM

I hope to get rid of these shimmies with replacing worn bearings and installing new slotted and drilled rotors. If this does not do it I will have to do the front control arems and tie rods next, wish me luck. I will update when the install is done.

The only issue I have is deciding what mufflers to putt on for dual exhaust. I want something loud but with a low tone, any suggestions is greatly appreciated.