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Headlight door motor retrofit overview

The original RS headlight door setup is complicated, unreliable, and expensive.  1967 was an electric system, 68 and 69 were vacuum-operated.  You can purchase aftermarket reproduction parts to re-create those.  There are also a couple of aftermarket retrofit kits available.

Here’s a relatively inexpensive retrofit that will operate the doors if you are not concerned about originality.


The core of the retrofit is the controller and motors from a 4th gen (1993-2002) Firebird.

Parts list – 4th gen Firebird:
– Pair of new replacement motors – $80
– Used headlight controller module – $70
– Used headlight wiring harness – $35 (optional)

– 3/16″ steel scrap for motor drive adapters
– Nuts, screws, washers for attaching motors
– two 10mm M6/1.5 nuts for motor shafts
– wire + connectors
– two inline fuse adapters with 15A fuses

The replacement motors are easy to find at auto parts stores or eBay.  I used the ones for the same model Firebird as the controller just to make sure everything is compatible, but a power window motor or a headlight motor from another vehicle should work also.

The controller module can be purchased new, but they are getting more expensive, and I found a good used one on eBay for much cheaper.  The controller works by running the motor until it senses the motor is drawing more current (because it has hit something) and then it will cut the power to the motor.  That means there’s no adjustments or timing to figure out, just hook the motor up to the doors and they’ll move until they hit the full open or full closed position.

The wiring harness is optional.  It was an easy way to get the 4-position and 5-position connectors that plug into the controller module.  You can buy them new, they are metripack connectors.


Here’s what the original Firebird schematic for the headlights looks like:

A few things to note from the schematic:

  • There are separate power feeds for the two motors.  The schematic shows that each one has a 15A fuse.  The benefit of having two separate fuses is that if one fuse blows, the other side will still work.
  • The controller module has relays inside it, so it is not necessary to add a relay or additional fuse between the controller and the motors.
  • The connector 1 position C wire is OPTIONALLY connected to the parking lights.  The normal behavior in the original Firebird application is that the lights pop up when the headlights go on, but they don’t retract until the parking lights go off.  The original Camaro setups (both vacuum and electric) had no connection to the parking lights, and only trigger on the headlight signal.  If you want it to behave as original, connect it to ground.  If you like the Firebird operation, connect this to the parking light power.  (Note that if you don’t connect it to anything, the doors will stay open all the time.)
  • The schematic shows the controller connected directly to the headlight and parking light circuits, so it is not necessary to add a relay or additional fuse to these connections.

The basic wiring consists of:
5-position connector #1 labeled ABCDE
– A1 – Headlight power signal – light blue wire between headlight and dimmer switches
– B1 and E1 – Always-on power through separate 15A fuses
– C1 -ground for Camaro behavior, connect to parking lights for Firebird behavior.
– D1  – ground

4-position connector #2 labeled ABCD
– A2 – Black lead motor 1
– B2 – Red lead motor 1
– C2 – Red lead motor 2
– D2 – Black lead motor 2
(I’m not sure if the wire colors are consistent on all replacement motors, but if the doors open with the lights off, and close with the lights on, swapping the red and black will fix that.)


The motor is attached to the headlight housing with two bolts and some spacer washers.  The placement is a bit of a compromise between centering the shaft in the hole, and leaving enough clearance for the motor and the gearbox.

With the motor in the right orientation, it hit one corner of the bracket.  Cutting a clearance notch allows the motor to sit level.

In order to get the holes lined up as accurately as possible, I marked and drilled one hole, then bolted the motor on, and then marked the second hole.


Attaching the Arm to the Motor

The bellcrank arm has a hole in the center that is almost the same size as the shaft on the motor.  The shaft has two flats on it that provide surfaces to turn the arm.  Unfortunately, the original bellcrank hole is too big to make a satisfactory matching oval hole out of.  I used a piece of 3/16″ scrap to make a plate that had the oval hole in it, and then attached that to the bellcrank with a couple of screws.  This spreads out the load and also allows it to sit lower on the shaft, which is closer to the stock location relative to the bracket.

To add the holes to the plate, I drilled and tapped one hole, then assembled it temporarily and drilled the second hole.

After the holes are drilled and tapped, I screwed the plate to the bellcrank arm from the back side so it would sit closer to the housing.  Assembling it in that order leaves some room underneath that prevents the arm from hitting the inner fender support structures.

Mounting the Controller

I used a couple of sheet metal screws to attach the controller to the radiator support just next to the regulator

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Headlight door motors

From what i can tell, this car was originally a base model (manual transmission) car.  The RS pieces are OEM, probably from a wrecked car.  The headlight doors did swing on their brackets, but none of the mechanism or wiring to open and close them were on the car when we got it.

The original 67 setup had electric motors and a bunch of relays and switches.  The 68-69 setup  Used vacuum actuators.  Getting the original stuff was going to be difficult and expensive, so I decided to go with something simpler.

After doing some research, I found that other people had used early 90’s Firebird headlight system components successfully.  I hit eBay and got a set of left and right replacement motors, a controller module, and a wiring harness.

1990-2002 Pontiac Firebird
– Headlight controller
– Headlight wiring harness
– Headlight motors

After stripping the unnecessary wiring out of the harness, I was left with 4 connectors and some wire.

It looks complicated, but it’s really fairly simple:

The controller has two connectors on it.

One connector has four wires, those go to two 2-wire connectors for left and right motor power.

the other connector has five wires on it, the two black ones go to ground, the two orange ones go to +12v (this should go through a 10a fuse), and the yellow one is a signal wire that should be connected to the low beam power wire of one of the headlights.

The nice thing about this setup is there’s nothing to adjust.  The controller powers the motor, the motor turns until it hits something, the controller senses the current draw go up because the motor isn’t able to turn, and the controller cuts power.  Connect the signal wire to +12 and the controller runs the motors one direction, cut the power to the signal wire and it runs them in the other direction.

for the first test I put an arm on the motor shaft and a bolt for the arm to run into (click picture to see video):

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Heater Core Repair

The weather here is getting cold, and although the heater is hooked up, the car wasn’t putting out any significant heat to the defroster or cabin.  I took it for a drive a few days ago, and noticed this on the garage floor:

Maybe it’s a loose hose connection inside the engine compartment?

looks damp, but…looking inside the car…

The core is leaking…no question about it.

I really hate plumbing and liquids in cars.  I always seem to make a mess no matter how careful I am.  I was determined to NOT make a mess this time, so I took some precautions.  It ended up working out really well!

First step: drain the radiator.  I threaded a piece of vinyl hose down to the bottom of the radiator, and used my mityvac to start a siphon into a trash can.

When I replaced the heater hoses this summer, it made a mess even though I was sure I had drained all the coolant out.  I decide to see if I could get more coolant out of the heater core before disconnected the hoses there.

Once it had drained below the level of the water pump, I disconnected the heater hose there.

…and clipped the corner off of a plastic bag so I could blow through it without getting dirt in my mouth.

That forced most of the liquid out of the heater core and into the lower hose…which drained back into the engine block, and was siphoned out with the rest of the coolant in the radiator.  After the coolant was finished draining, I removed the heater hoses from the heater core pipes, and…no mess.  Nothing came out when I disconnected the hoses.

To be extra sure, I put the vinyl hose into the lower pipe, and used the mityvac to suction out any coolant I could get.  I didn’t end up getting anything out, which means forcing the coolant out worked great!

I knew the next step would involve tipping the heater core out to get the pipes out from the firewall holes, and I didn’t want to spill anything, so I rolled up some paper towels and threaded them into the heater core pipes to at least slow down anything that was going to come out.

The next step is taking off the 5 speed nuts holding the heater box onto the firewall.  Good news/bad news, there were only two nuts installed on the car, so that went a lot easier than it should have.

Moving to the interior, I put down a big sheet of plastic over the carpet, and put an old towel on top of that to soak up any spills.

Getting the housing out was not simple.  I did not take out the glovebox, I did not take out the console, I did not disassemble the center dash section.  All three of these would have made the job easier, but so far it isn’t 100% necessary.  I may need to do some or all of those things for reassembly, but I don’t know yet.

Things that can and should be disconnected:
– The fan wiring plug on top of the housing should be unplugged
– The plastic diverter piece that sits in the center of the transmission tunnel
– The climate control cables that are attached to the housing.

A tiny 5/16″ ratchet box wrench was the only way to get the mounting screws out of the plastic diverter housing.  It was difficult even with that tool.  There are several screws that need to be removed.

I didn’t disconnect the cables entirely, mostly because I couldn’t get the circular cable end off of the pegs they were on.  I decided I’d be able to get to them easier after it was out from under the dashboard.  I did disconnect the mounting brackets that I could get to.

Once those cables were loosened, I was able to pull the housing out to the passenger side.  This left the core still in the firewall half of the housing, which means it unsnapped itself from the brackets that hold it into the passenger half of the housing.  I’ll worry about that later.  I was not able to get the housing completely off because it is still attached to the cables…but I have a better shot at removing them now.

I was able to get the heater core out after the housing was out of the way.  Amazingly, I did not spill any coolant getting it out.  That’s a huge win in my book as I didn’t want to make a mess of the carpet or the garage floor.

It does not say “Harrison” on it, so I do not think it is original.  Because it’s a replacement, I’m not sure it’s worth having it re-cored.  Not so much for originality, but just design.  An original recore should work and fit better than a cheap modern reproduction.

Not surprisingly, there was a huge mouse nest in the housing, which explains why there wasn’t any significant heat coming out.  No airflow!

I’ll clean this out and paint it to prevent further damage before I put it all back together.

Stay tuned…