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This answer is applicable for many BMWs in addition to the one listed below.
Q
car year: 1989
car model: 325i
I think it is a ground cable, it’s braided looking, but what is the cable that connects to my front hood to the chassis for. It’s ripped. Do I need a new one?
A
The small braided cable that connects from the underside of the front of the hood to the front radiator support structure is a grounding strap. The purpose is to assure proper grounding of the vehicle hood for electrical continuity and to prevent radio interference. We do keep these in-stock.
Hood to chassis grounding strap (E30 3-series 84-91):
Q car year: 2006
car model: 330i
My battery is the original in the car. (e90) Last winter and now this winter it seems that this battery is on its way out. I am researching the proper way to replace the battery. Is this a “dealer-only” thing? I thought i read somewhere that the car has to be programmed to see the new battery or something. What would happen if i just replaced the battery myself (like every other car i have owned)? Please explain the correct steps to replace the battery on this car. I see that it has the bracket over it and the 2 terminals, but there is an extra module or something over the positive post.
A
See the link below for general information on late model BMW battery replacement issues.
Click HERE for battery replaement and registering info.
Additionally, to address your specific questions:
The positive cable has a Battery Safety Terminal (BST) the is a power disconnect device. The disconnect is activated via the Multiple Restrain System (MRS) module, in the event of a crash.
The negative cable carries the Intelligent Battery Sensor (IBS). The IBS monitors battery conditions.
Finally, there is the rear power distribution panel, which is mounted on top of the battery.
Disconnect the negative and positive cable clamps and lift the cables, clamps and the rear power distribution panel off the battery and lay the assembly aside. You can now remove the battery hold-down (at rear of battery), disconnect the vent hose and lift the battery out.
This answer is applicable for many BMWs in addition to the one listed below.
Q
car year: 1991
car model: 325i Convertible
When I turn the ignition key on three of the green service interval lights come on but when I start the engine the green lights go out but then the yellow oil service light flickers. Also last week the obc light got very dim then went out. Could I have a wiring problem or two unrelated problems happened at the same time?
A
This answer is applicable to most ’80s model BMWs; 318i, 318is, 318ic, 325, 325e, 325es, 325i, 325is, 325ic, 325ix, 528e, 533i, 535i, 535is, M5, 633csi, 635csi, L6, M6, 733i, 735i, 745i, L7.
Have you attempted to reset the oil service indicator? While the indicator lights do not typically flicker, it may be that you need to reset the indicator in order for the yellow light to reset. If the light (lights) will not reset, and stay reset, you may need to replace the Service Interval Circuit Board, in the instrument cluster. We do offer two options in tools that will reset the oil and the inspection reminder lights. One tool just does these resets, the other tool will also read and reset the engine management fault codes. See the links below.
Reset tools (after clicking link, ID your BMW model to see which tools work for your model):
Service Interval PC boards:
The lighting for the OBC is likely just a failed illumination bar. These are easily replaced. See the article and Fast Times Newsletter DIY at the link below.
Click HERE for BMW OBC illumination info & DIY link
OBC illumination bar:
