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Thanks for the detailed write-up, UM Rebel!
I am thinking of attempting this fix (checked my HCM using your procedure), but am wondering how you relocated your new module to the fuse box and battery box.
I am assuming you soldered the wires that connected to the original HCM together at the passenger headlight and then spliced in earlier/closer to the fuse box? If that's correct - which wires were connected at the passenger headlight? And which wires were connected to your new HCM?
I can figure out that to splice in earlier, I will trace back the harness and pull A/B/C/D/E to connect as you've labelled them onto my new HCM, but then I'm left with a 4 pin connection and 2 posts. Which go where? And I've got the same problem at the passenger headlight - 5 wires to connect to 4?
I'm comfortable with mechanical fixes, but electrical is not my forte. No better way to learn than to do though! Any help would be appreciated. Thanks!
The 4 pin goes to the two posts, two to each post. On the original HCM, the motors are wired to the HCM individually, 2 per motor. This method combines the connections.
The 4 pin goes to the two posts, two to each post. On the original HCM, the motors are wired to the HCM individually, 2 per motor. This method combines the connections.
Yeah, but I'm having a hard time figuring out which 2 wires go to each post, and how I would go about closing the circuit at the passenger headlight. If I figure that part out, I could make my HCM, put it in the original location to ensure I've built it properly and everything works, and then splice it in at the fuse box later on (to prevent water damage issues). That way I can troubleshoot much easier since I'm new to electrical fixes.
Yeah, but I'm having a hard time figuring out which 2 wires go to each post, and how I would go about closing the circuit at the passenger headlight. If I figure that part out, I could make my HCM, put it in the original location to ensure I've built it properly and everything works, and then splice it in at the fuse box later on (to prevent water damage issues). That way I can troubleshoot much easier since I'm new to electrical fixes.
Dark Blue and Dark Green wires go together on one post.
Light Blue and Light Green wires go together on the other post.
If it works backwards, that is, if doors close when you turn lights on and vice versa just swich both sets of wires to other posts.
You guys have some mad skills. Very impressive and thanks for posting, even if many of us (myself included) will probably never tackle anything like this
Dark Blue and Dark Green wires go together on one post.
Light Blue and Light Green wires go together on the other post.
If it works backwards, that is, if doors close when you turn lights on and vice versa just swich both sets of wires to other posts.
Thanks so much! Hopefully I can get my feet wet and learn a new skill!
Does anyone know how much current needs to be seen by the HCM for them to work correctly? This has to do with putting low current draw LED's and the headlights won't flip down?
I want to add some HID's that are a separate circuit using relays/harness and pulling power from the battery for function. I want to make sure that the headlight will flip up/down like normal.
I repaired mine but I went about it in a different way.
Only one side of my lights seemed fried and the other side seemed fine. So I spliced the left and right wires together (whatever was the working side - it's been so long I don't remember) outside of the unit and they both go up and down together.
Sometimes after a few cycles they get out of alignment so I re-sync them. It works for the few times I use the headlights anymore. For those times there is the manual wheel.
Does anyone know how much current needs to be seen by the HCM for them to work correctly? This has to do with putting low current draw LED's and the headlights won't flip down?
I want to add some HID's that are a separate circuit using relays/harness and pulling power from the battery for function. I want to make sure that the headlight will flip up/down like normal.
It's been years since I've done similar to what you want to do. I have 85w HIDs that draw from the stock circuit and then directly from the battery when switched to high beam to continue to power them in addition to high beam LEDs. I had issues with my motors that I thought were being caused by the low draw HIDs (though they do have a high draw upon start-up). While troubleshooting, I seem to recall the motor circuit only needing 1 or 2 amps to open and they spike to around 9 amps when hitting the stoppers, which signals to the controller that they've reached the max travel up or down. For my particular ballasts I did not need anything additional for them to work with the stock circuit. Once in a while one of the motors won't trigger properly but it's infrequent enough that it hasn't been worth the effort to add resistors or do anything else to create more of a draw and I simply cycle the switch again. I'm fairly certain if you target ~3 amps it would be reliable - but I'm recommending on a hazy memory!
It's been years since I've done similar to what you want to do. I have 85w HIDs that draw from the stock circuit and then directly from the battery when switched to high beam to continue to power them in addition to high beam LEDs. I had issues with my motors that I thought were being caused by the low draw HIDs (though they do have a high draw upon start-up). While troubleshooting, I seem to recall the motor circuit only needing 1 or 2 amps to open and they spike to around 9 amps when hitting the stoppers, which signals to the controller that they've reached the max travel up or down. For my particular ballasts I did not need anything additional for them to work with the stock circuit. Once in a while one of the motors won't trigger properly but it's infrequent enough that it hasn't been worth the effort to add resistors or do anything else to create more of a draw and I simply cycle the switch again. I'm fairly certain if you target ~3 amps it would be reliable - but I'm recommending on a hazy memory!
Hey all, thanks for sharing this diagram and solution.
I have an 85 Firebird with the 3 wire motors and replacements for these are either very rare, or very expensive, especially here in Australia.
The cheaper option for me was to upgrade to 87-89 firebird 2 wire motors and find a headlight motor module to run them and this is the perfect cheap solution.
I'm not great at reading wiring diagrams so I've recreated it and colour coded it to identify where wires are connected and where they are just overlapping in your diagram.
Are you able to confirm if the below is correct?
Also to confirm, when the headlight is turned on, 12v is sent to the ON terminal, and when the headlight switch is turned off, it sends 12v to the OFF terminal?, or ground?
I'm using a different headlight switch, so mine is 12v for low/high beam, and open when it's off so I may need to modify it to work.
Hey all, thanks for sharing this diagram and solution.
I have an 85 Firebird with the 3 wire motors and replacements for these are either very rare, or very expensive, especially here in Australia.
The cheaper option for me was to upgrade to 87-89 firebird 2 wire motors and find a headlight motor module to run them and this is the perfect cheap solution.
I'm not great at reading wiring diagrams so I've recreated it and colour coded it to identify where wires are connected and where they are just overlapping in your diagram.
Are you able to confirm if the below is correct?
Also to confirm, when the headlight is turned on, 12v is sent to the ON terminal, and when the headlight switch is turned off, it sends 12v to the OFF terminal?, or ground?
I'm using a different headlight switch, so mine is 12v for low/high beam, and open when it's off so I may need to modify it to work.
Ok, well I managed to make it, I just need to test it and I guess use a 3 way switch in place of my current headlight switch to send the 12v signal to either open or close the headlight doors.
If anyone figured out a way to have the doors close when there is no 12v signal, please let me know.
I tidied up the wiring a bit and grouped some of the 12v and grounds as I'll be using constants direct from battery for these and then just running the 12v oopen and 12v close from the existing wiring harness on my TransAM.
