1990 Heater Blend door actuator help
Thread Starter
Pro
Joined: Jan 2006
Posts: 571
Likes: 29
From: Delanson New York
1990 Heater Blend door actuator help
I am looking for someone who has had the misfortune to need to replace the blend door actuator for the HVAC system on a 1990 MY. I have got to the point as seen in the pictures and it seems like you need to remove the air distribution duct which spans the width of the car. The service manual says I need to remove the instrument panel to remove the duct.
Has anyone replaced the actuator without removing the entire IP from the car? I've got to believe someone out there has. I would appreciate any help or guidance you can offer. Thanks.
Has anyone replaced the actuator without removing the entire IP from the car? I've got to believe someone out there has. I would appreciate any help or guidance you can offer. Thanks.
Burning Brakes
Joined: Sep 2008
Posts: 810
Likes: 58
From: Alva Florida
I did this job a while back. I drilled the rivets out and replaced with nuts/bolts/washers.
It allowed me to take the right half of the dash out. I replaced my heater core though. I was able to get the a/c box out without taking the whole dash out.
I had a terrible time "clocking" the actuator. The Dorman blend door actuator wouldn't work on my car, and I believe the 1990-1993 are different. Ended getting an actuator and harness from a 1994-96 to make it work. Very frustrating.
Also, be careful with the electrical connectors when disassembling. I didn't mark with tape "A" to "A","B" to "B" etc. Then I found out the plugs are interchangeable and luckily someone here helped me out.
It allowed me to take the right half of the dash out. I replaced my heater core though. I was able to get the a/c box out without taking the whole dash out.
I had a terrible time "clocking" the actuator. The Dorman blend door actuator wouldn't work on my car, and I believe the 1990-1993 are different. Ended getting an actuator and harness from a 1994-96 to make it work. Very frustrating.
Also, be careful with the electrical connectors when disassembling. I didn't mark with tape "A" to "A","B" to "B" etc. Then I found out the plugs are interchangeable and luckily someone here helped me out.
Last edited by cadmaniac; Nov 5, 2017 at 02:57 PM.
Thread Starter
Pro
Joined: Jan 2006
Posts: 571
Likes: 29
From: Delanson New York
I did this job a while back. I drilled the rivets out and replaced with nuts/bolts/washers.
It allowed me to take the right half of the dash out. I replaced my heater core though. I was able to get the a/c box out without taking the whole dash out.
I had a terrible time "clocking" the actuator. The Dorman blend door actuator wouldn't work on my car, and I believe the 1990-1993 are different. Ended getting an actuator and harness from a 1994-96 to make it work. Very frustrating.
Also, be careful with the electrical connectors when disassembling. I didn't mark with tape "A" to "A","B" to "B" etc. Then I found out the plugs are interchangeable and luckily someone here helped me out.
It allowed me to take the right half of the dash out. I replaced my heater core though. I was able to get the a/c box out without taking the whole dash out.
I had a terrible time "clocking" the actuator. The Dorman blend door actuator wouldn't work on my car, and I believe the 1990-1993 are different. Ended getting an actuator and harness from a 1994-96 to make it work. Very frustrating.
Also, be careful with the electrical connectors when disassembling. I didn't mark with tape "A" to "A","B" to "B" etc. Then I found out the plugs are interchangeable and luckily someone here helped me out.
Are you talking about having drilled out the 5 or 6 rivets just left of the blue tape on the orange and white wire? Thanks again.
Burning Brakes
Joined: Sep 2008
Posts: 810
Likes: 58
From: Alva Florida
Yes, the 4 Rivets to the left of the blue tape. It's still a difficult job mind you. There is a duct (tube) that goes inside the box that is a nuisance to put back in.
Now that I think of it, I replaced the whole heater box with one out of a 94-96 (with the small harness), and now my actuator is on the bottom like the newer models. I mention this because it I don't know if it is commonly known, and in the future it will be very easy to service that actuator.
Hope this helps a bit.
Now that I think of it, I replaced the whole heater box with one out of a 94-96 (with the small harness), and now my actuator is on the bottom like the newer models. I mention this because it I don't know if it is commonly known, and in the future it will be very easy to service that actuator.
Hope this helps a bit.
Last edited by cadmaniac; Nov 6, 2017 at 07:18 AM.
Thread Starter
Pro
Joined: Jan 2006
Posts: 571
Likes: 29
From: Delanson New York
If you have any thoughts on how to make the repair I would appreciate hearing them.
Thanks.
Last edited by jrd1990zr1; Nov 6, 2017 at 10:22 AM.
Burning Brakes
Joined: Sep 2008
Posts: 810
Likes: 58
From: Alva Florida
29 years for any car before needing a repair is not a "repeat event".
However, now I remember what I did (I'm old, I suppose and its been a while since I did this repair). I couldn't clock the used 1990-1993 actuator no matter how hard I tried. I was frustrated....so I got on the auction site and ordered the box and harness (90-93 I believe the actuator is on the top and 94-96 the actuator is on the bottom of the footwell so you can service it) and ended up using the Dorman part.
Just mark the harnesses and you will be fine. Take your time and don't force anything. Plastic breaks easily. and some of the vents screw in from behind. I liked taking out the right half of the dash because I didn't have to lie on my back and do it upside down. It was easy to do except putting it together like factory was challenging. I ended up using a lot of zip ties to make it all fit right because once you take it apart, it is a huge mess of wiring and relays.
I was hesitant to approach this job, but I took my time and it wasn't that bad except for clocking and re-working it to the newer design.
However, now I remember what I did (I'm old, I suppose and its been a while since I did this repair). I couldn't clock the used 1990-1993 actuator no matter how hard I tried. I was frustrated....so I got on the auction site and ordered the box and harness (90-93 I believe the actuator is on the top and 94-96 the actuator is on the bottom of the footwell so you can service it) and ended up using the Dorman part.
Just mark the harnesses and you will be fine. Take your time and don't force anything. Plastic breaks easily. and some of the vents screw in from behind. I liked taking out the right half of the dash because I didn't have to lie on my back and do it upside down. It was easy to do except putting it together like factory was challenging. I ended up using a lot of zip ties to make it all fit right because once you take it apart, it is a huge mess of wiring and relays.
I was hesitant to approach this job, but I took my time and it wasn't that bad except for clocking and re-working it to the newer design.
Last edited by cadmaniac; Nov 7, 2017 at 07:14 AM.
Thread Starter
Pro
Joined: Jan 2006
Posts: 571
Likes: 29
From: Delanson New York
29 years for any car before needing a repair is not a "repeat event".
However, now I remember what I did (I'm old, I suppose and its been a while since I did this repair). I couldn't clock the used 1990-1993 actuator no matter how hard I tried. I was frustrated....so I got on the auction site and ordered the box and harness (90-93 I believe the actuator is on the top and 94-96 the actuator is on the bottom of the footwell so you can service it) and ended up using the Dorman part.
Just mark the harnesses and you will be fine. Take your time and don't force anything. Plastic breaks easily. and some of the vents screw in from behind. I liked taking out the right half of the dash because I didn't have to lie on my back and do it upside down. It was easy to do except putting it together like factory was challenging. I ended up using a lot of zip ties to make it all fit right because once you take it apart, it is a huge mess of wiring and relays.
I was hesitant to approach this job, but I took my time and it wasn't that bad except for clocking and re-working it to the newer design.
However, now I remember what I did (I'm old, I suppose and its been a while since I did this repair). I couldn't clock the used 1990-1993 actuator no matter how hard I tried. I was frustrated....so I got on the auction site and ordered the box and harness (90-93 I believe the actuator is on the top and 94-96 the actuator is on the bottom of the footwell so you can service it) and ended up using the Dorman part.
Just mark the harnesses and you will be fine. Take your time and don't force anything. Plastic breaks easily. and some of the vents screw in from behind. I liked taking out the right half of the dash because I didn't have to lie on my back and do it upside down. It was easy to do except putting it together like factory was challenging. I ended up using a lot of zip ties to make it all fit right because once you take it apart, it is a huge mess of wiring and relays.
I was hesitant to approach this job, but I took my time and it wasn't that bad except for clocking and re-working it to the newer design.
I am also thinking of going the 94-95 route since it seems this may be the better way to deal with it. Also going to have the CDM serviced since I have it removed.
Thanks again, John
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