Frequently Asked Questions - BMW M coupe Volt Meter
What information does the voltmeter tell us?
- If the motor is running and the voltage is not at 14V, you could have a bad alternator, or a severely discharged battery, or a slipping belt.
- If the voltage is not near 12V when you first turn the key, but before starting the car, you may have a weak, or partially charged battery.
- If the voltage goes up to near 14V when you rev the motor, but drops closer to 12V when you let it idle, you may have a large load (things turned on), a slipping alternator belt, or a weak alternator (usually bad diodes, or slip rings).
- If the voltage goes up over 14V reaching 15V or more with the motor running, you have a bad voltage regulator (usually inside the alternator), and it will damage the battery if not corrected soon.
How do I install the Volt Meter into a BMW M coupe?
The following instructions are for installing a Volt Meter in place of the blanking plate in BMW M coupes. I received the parts and a set of instructions from the dealership. Below is a summary of the instructions along with additional wording for clarification.
Parts and Tools Required
62-13-2-695-215 voltmeter
62-13-2-695-217 bulb socket
62-13-2-695-218 bulb 12volt 2watt
Long flat blade screwdriver, 16 inch long blade or longer
Phillips screwdriver
Assemble Volt Meter
- Install bulb into bulb socket
- Install bulb socket into volt meter
- Make sure O-ring is in grove on the volt meter, about a 1/2 inch in from the front of the meter
- Unscrew retaining collar from volt meter
Remove Blanking Plate
- Remove caps and screws to the passenger side center console.
- Pull down and then back on the right side center console panel to gain access. The panel does not pull off, it will only give you enough room to get your hands in.
- Using long flat screwdriver, reach in with blade to tap loose the retaining collar. Place blade at the bottom of the retaining collar to contact one of the edges of the retain collar.
- Now hit the other end of the screwdriver to cause the retaining collar to come loose.
- Once loose, unscrew the collar and remove the blanking plate.
Connecting and Installing Volt Meter
- Volt Meter wire harness is inside the center console. The wire harness has three unconnected connectors. (When I did this, the harness was laying right in front of me when I opened up the passenger side center console.) Place collar from volt meter inside center console and pull the Volt Meter wire harness through the collar.
- Position collar behind center console opening for volt meter, so the Volt Meter wire harness is through the opening to allow the connection to the volt meter.
- Three (3) connections are made to the back of the volt meter; double black connector goes to light bulb, violet/yellow or green/yellow wire goes to "+" connector, brown wire goes to "-" (ground) connector.
- Push volt meter and wire harness back through center console. Meter should now rest flat, against center console. Meter and center console are keyed.
- Screw collar onto the volt meter and hand tight.
- Check to make sure all connections are on inside the center console.
- Turn on headlights to check console lighting, start engine to check volt meter.
- Reinstall console panel and screws.