Voltage

I noticed the other day that the heater fan motor seemed to be slowing down and speeding up, according to engine RPM. I checked the voltage on the DIC and it is showing 14.8 at speed and 12 at idle........ It seems like that it used to be at 14+ volts all the time.....what does yours show at idle? BTW at that time the headlights, fog lights and heater fan
( High) were all on........
Thanks
Jim

I have a 1997 Aurora. The voltage in my car began fluctuating several months ago. However, the voltage fluctuations in my car cause the tachometer to bounce eratically. I have replaced the alternator, battery, & ignition control module. None of these have worked. Please let me know if you figure out what is causing it.

I didnt have any of those symptoms. I found the antenna was frozen. Since I fixed that, the voltage stays right around 15 now.

my subwoofer amplifier is high current draw, and without a capacitor, i was running at about 13.8 even with it turned down all the way (if i'd switch it all off, then i'd be around 14.8). i added a capactor today, and i'm constantly around 15.5, which is an added bonus.

97 aurora with dipping tachometer when I'm slowing down to a stop. This only happens when I'm decelerating slowly. This just started after fuel pump was replaced due to a recall. Since then have had the throttle plate cleaned and repositioned at the dealer, but tach still dips way low when slowing down.

I finally fixed the voltage fluctuations in my 97. The tachometer in my car is working perfect. I purchased a year subscription to alldatadiy.com for $15.00. At the alldatadiy site you can select electrical diagrams for the Aurora. I printed out all of the grounding locations on the car and printed them out. I simply tightened all of the ground points on the car and the problem is gone. :smile: