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I have a 2005 Buick Rainier. The headlights keep popping on and killing my battery. Would this be caused from the bcm needing to be replaced or headlamp relay?

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Probably the HDM - headlamp driver module .
The headlamp driver module (HDM) is an electronic module that provides electrical power to the vehicle low beam headlamps. The HDM is controlled by a pulse width modulated (PWM) ground signal from the body control module (BCM). The BCM determines the desired lamp intensity using the ambient light sensor, multifunction switch and the park brake switch as inputs. In general, the HDM will operate in 1 of 3 modes:
• Reduced Intensity Mode: This mode is used by features that do not require or allow maximum low beam headlamp intensity such as daytime running lights (DRL) (nominal: 85% duty cycle).
• Full Intensity Mode: This mode is used by features that require full low beam headlamp intensity such as low beam headlamp operation in manual or auto modes (nominal: 100% duty cycle).
• Off Mode: This is the default mode of the system that will occur when none of the features described above are active. The BCM will deactivate its PWM output (0% duty cycle) during this mode.

HDM is a relay located in the under hood fuse box . #46

Posted on Jul 12, 2019


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Posted on Jan 02, 2017

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SOURCE: How to replace a headlamp on 2005 VW Beetle

Are you still looking for help with replacing headlights for 2005 VW.
If so , I have to replace mine tomorrow , I can photograph the process if that helps..

Posted on Mar 10, 2009

  • 383 Answers

SOURCE: 2005 Altima headlamp replacment

fsu3: go to mybunkey and you will find explicit directions on replacing the bulbs and headlight Assembly's on your car.

Posted on Apr 07, 2009

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SOURCE: How do I locazte/replace the air filter in my 2004 Buick Rainier

Hi. the air filter is in a cylindrical looking device that is connected to the intake throttle body, via plastic flex hose. it runs horizontal. you will have to un clip the plastic housing and extract the filter. i will post a picture below.


Posted on May 22, 2009

  • 630 Answers

SOURCE: How do you replace a low-beam headlight on the 2005 Buick Rainier

Most vehicles are equipped with Halogen bulbs that are small bulbs that are replaced from under the hood behind the headlight bezel assembly.
They have a twist turn method generally to remove/replace hiowever they cannot have your hand come in contact with the glass bulb as the oils on your skin will in fact reduce the halogen bulbs life as it gets extremely hot burning the oil off the lense shortening the bulbs existence.
Remember to replace the bulb with the proper bulb as you may find two or three different applications of halogen bulbs for the same vehicle, they all have a purpose, they go from bright to brighter to brighter each increase in candle power also increases in price of the bulb, a typical standard priced Halogen is approximately $9.95 and up.

Posted on May 09, 2010

  • 6927 Answers

SOURCE: I have a 2005 Buick Rainier. The A/C unit has a

The ac system has to be reset,removal of the fuse for the ac,will do this,leave it out for about 10 seconds then replace it,removal of the negative battery cable will most likely do it,but,the computer for the vehicle might loose it`s memory if you do this,unless you have had the battery out before,and know that it will not,after reseting the ac system,have the ac gauges put on the car,and see what the readings will tell,there is a problem there somewhere or the ac system would not shut down,the system while not running,it is hard to tell if there is enough freon ,or not,but check it with the gauges to tell for sure what the problem is.

Posted on May 28, 2010

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