WTB Headlight Door Control Module (Page 1/2)
gregr75 AUG 18, 12:44 PM
1987 (gen 2) headlights work fine except right headlight door doesnt lift up when headlight switch engaged. diagnosed everything works except control board per service manual.

taking it apart there's no obvious signs of damage or blown fuses.

do they sell these things new? I see them on eBay for sale but not sure if they are new or used. i'd rather get a new unit then something from another 87 fiero. I see GM used these on other cars during the era, but there is a little bit of incompatibility with some control modules per this thread

https://www.fiero.nl/forum/...130314-2-095675.html

My control board is dated 10-87 and is part number 16509737-2.

if anyone has any links or info that would be appreciated
cartercarbaficionado AUG 18, 03:04 PM

quote
Originally posted by gregr75:

1987 (gen 2) headlights work fine except right headlight door doesnt lift up when headlight switch engaged. diagnosed everything works except control board per service manual.

taking it apart there's no obvious signs of damage or blown fuses.

do they sell these things new? I see them on eBay for sale but not sure if they are new or used. i'd rather get a new unit then something from another 87 fiero. I see GM used these on other cars during the era, but there is a little bit of incompatibility with some control modules per this thread

https://www.fiero.nl/forum/...130314-2-095675.html

My control board is dated 10-87 and is part number 16509737-2.

if anyone has any links or info that would be appreciated


firebird and corvettes have them
Vintage-Nut AUG 18, 04:49 PM

quote
gregr75:
do they sell these things new?



YES, GM STILL Offers the Part!
MODULE, Concealed Capsule/Headlamp Control
GM 16523917 {Replaces 16505400 and 16521297}

https://www.maloufpartsxper...arch_str=GM+16523917

------------------
Original Owner of a Silver '88 GT
Under 'Production Refurbishment' @ 136k Miles

[This message has been edited by Vintage-Nut (edited 08-18-2024).]

Dennis LaGrua AUG 18, 04:49 PM
The Gen II modules can be repaired. There is a 14 pin multi-pole relay in them that can be replaced. Omron P/N MY4-02 12VDC Power Relay 14Pins. About $22 on eBay. Its a soldering job replacing it but doable.
New modules are available but quite expensive. If you want to buy new just match the GM part number,

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

Larryinkc AUG 18, 07:19 PM
Here's a vid for the relay replacement.

https://www.youtube.com/watch?v=iyviCvw0o8I
Vintage-Nut AUG 18, 10:23 PM
FYI: Properly unsoldering and soldering is a Skill with the correct tools.

Not too cold; not too hot but the perfect temperature and the time for the subject....

Hint: Do not 'overcook' the solder pads from the PCB!
gregr75 AUG 19, 12:42 AM

quote
Originally posted by Vintage-Nut:


YES, GM STILL Offers the Part!
MODULE, Concealed Capsule/Headlamp Control
GM 16523917 {Replaces 16505400 and 16521297}

https://www.maloufpartsxper...arch_str=GM+16523917



wow, $376,,, yeesh! And although it says its good for the fiero, it lists 16523917, 16505400 and 16521297, none of which are my PN (16509737-2). BTW I'm reading the number printed directly on my circuit board after removing the plastic cover.

I saw this link for a guy on ebay who it seems makes these from scratch, but again, doesnt list my board PN. i emailed him.
https://www.ebay.com/itm/40...5:g:qDAAAOSwat9lQWsk

BTW the relay on my board is fine, I see it clicking on and off when flicking the headlight switch.

[This message has been edited by gregr75 (edited 08-19-2024).]

jelly2m8 AUG 19, 01:36 AM
It's the same part used on Corvette's, its readily available
Mike in Sydney AUG 19, 10:34 AM
Just replaced the module on my ‘86 SE. (I converted to the ‘87-‘88 system earlier.). I had the same symptoms as you except it was the left side headlight. I replaced mine with a module for a ‘94 C4 Corvette. Cost $125 USD. Problem solved!

BTW, I tried replacing the motors first since I had a couple of spare version 2 motors.

[This message has been edited by Mike in Sydney (edited 08-19-2024).]

gregr75 AUG 19, 01:00 PM
So a 94 corvette module worked with your 1986 fiero motors? Interesting. where did you buy the module from?

i'm hesitant to buy a Corvette module because the original thread I referenced, 4th post down from Dodgerunner said some people were having problems getting it to work with their fiero, until they bought a "fiero specific" module.