Headlight Door Not Opening
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Joined: Dec 2015
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From: Smithtown New York/Naples Florida/Flint Twp. Michigan
Headlight Door Not Opening
The headlight doors on my 2001 vert with 72,000mi on it will not open when the headlights come on. The headlight door control module is receiving the on signal from the multi function turn signal switch when in the headlight on position and the off signal when in the off position with twilight off. When twilight is on the HDCM receives both the on and off signal from the MFTS. The HDCM sends out a signal on both the up and down terminals for both doors at all times. I have two questions. Shouldn't the HDCM only send out a signal for up when lights are on and down when off and should the twilight setting send both on and off signals at the same time? Ignition switch has been rebuilt and grounds have been cleaned. There are only two codes that reoccur every time they are cleared. They are BO-RFA 1000H and 1064H. I don't believe they have anything to do with the headlight door issue and plan to address them at a later date. I'm thinking that the HDMS has failed but wonder if the MFTS should be sending both on and off signals at the same time. I would like to make sure I am making the correct repair without guessing. Anyone have the answers to these two questions?
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Joined: Dec 1999
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Here is a POWER side of the HDMS. There is also a schematic of the control side.
The HDMS always applies power to one motor or the other. The Head light assembly does not have limit switches. The HDMS senses a raise in drive current when the module enters the UP- or Down limits and the HDMS stops driving the motor.
The HDMS always applies power to one motor or the other. The Head light assembly does not have limit switches. The HDMS senses a raise in drive current when the module enters the UP- or Down limits and the HDMS stops driving the motor.
Thread Starter
Advanced
Joined: Dec 2015
Posts: 85
Likes: 27
From: Smithtown New York/Naples Florida/Flint Twp. Michigan
Here is a POWER side of the HDMS. There is also a schematic of the control side.
The HDMS always applies power to one motor or the other. The Head light assembly does not have limit switches. The HDMS senses a raise in drive current when the module enters the UP- or Down limits and the HDMS stops driving the motor.
The HDMS always applies power to one motor or the other. The Head light assembly does not have limit switches. The HDMS senses a raise in drive current when the module enters the UP- or Down limits and the HDMS stops driving the motor.
