73 Kickdown Diagnostics
Thread Starter
Instructor
Joined: Jun 2021
Posts: 213
Likes: 45
From: Georgia
73 Kickdown Diagnostics
Hello,
I'm trying to diagnose my non working kickdown.
The kickdown switch behind the dash is activating the hood door for the cold air, however, I do not hear the solenoid on the tranny engaging.
So, I have several problems/questions.
- If the switch is activating the hood door, does that mean the switch is good and the solenoid is bad?
- The switch only goes down 3/4 way when fully compressing the gas pedal (which does not activate the hood door). I had to use my hand to fully compress the switch in order to engage the hood door. I do not visibly see a way to adjust the switch, it does sit on a bracket, should i just bend that bracket?
Thanks in advance for your help.
Eric
(I originally posted this in "General", I think it belongs here, I'll try to delete that thread.)
I'm trying to diagnose my non working kickdown.
The kickdown switch behind the dash is activating the hood door for the cold air, however, I do not hear the solenoid on the tranny engaging.
So, I have several problems/questions.
- If the switch is activating the hood door, does that mean the switch is good and the solenoid is bad?
- The switch only goes down 3/4 way when fully compressing the gas pedal (which does not activate the hood door). I had to use my hand to fully compress the switch in order to engage the hood door. I do not visibly see a way to adjust the switch, it does sit on a bracket, should i just bend that bracket?
Thanks in advance for your help.
Eric
(I originally posted this in "General", I think it belongs here, I'll try to delete that thread.)
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,117
From: Crossville TN
The kickdown switch merely passes 12vdc to the solenoid on the hood scoop and to the detent solenoid inside the transmission. You can check for 12vdc coming to that switch, then coming out of it and getting TO the other devices. If you find that the switch is sending power to the door solenoid and into the transmission, any problems beyond that would be due to the devices, themselves. For the trans kickdown solenoid, you could just send 12vdc (also ground the trans housing) into the connector at the trans to listen for the solenoid 'click'. If you don't hear it, the detent solenoid inside the trans (mounted with 2 bolts on underside of channel plate), either the solenoid is bad or the wiring going to it is broken. you could also check resistance of the detent solenoid coil: + to housing connector and - to housing. If you get an 'open' circuit, it could be the solenoid or broken wiring.
Last edited by 7T1vette; Jul 27, 2021 at 02:00 PM.
Thread Starter
Instructor
Joined: Jun 2021
Posts: 213
Likes: 45
From: Georgia
The kickdown switch merely passes 12vdc to the solenoid on the hood scoop and to the detent solenoid inside the transmission. You can check for 12vdc coming to that switch, then coming out of it and getting TO the other devices. If you find that the switch is sending power to the door solenoid and into the transmission, any problems beyond that would be due to the devices, themselves. For the trans kickdown solenoid, you could just send 12vdc (also ground the trans housing) into the connector at the trans to listen for the solenoid 'click'. If you don't hear it, the detent solenoid inside the trans (mounted with 2 bolts on underside of channel plate), either the solenoid is bad or the wiring going to it is broken. you could also check resistance of the detent solenoid coil: + to housing connector and - to housing. If you get an 'open' circuit, it could be the solenoid or broken wiring.
2026 Loser of the Year
Joined: Sep 2013
Posts: 36,582
Likes: 7,031
From: New Or-leens Loo-z-anna
Sometimes drivers tend to "stomp" the gas pedal all the way to the floor, rather than Pressing the gas pedal....this will cause the switch to "get out of adjustment".
I would think the plunger needs to be depressed nearly all the way or at least 80% depressed...rookie guess.
Advanced
Joined: Sep 2012
Posts: 88
Likes: 45
From: Littleton Colorado
I had the same issue with my 73 and it ended up being a bad solenoid. Double check that the wire is connected to the solenoid at the trans, it can slip off. If you’ve got a test light you can also check to see if it’s getting power when you activate the switch at the pedal. If it is and you’re still not getting kickdown a replacement may be in order. It’s not difficult to swap out the old for a new one. Just drop the trans pan and unbolt the solenoid from within and replace with new. There are 2 small bolts that secure it. It took me less than an hour. I got the solenoid from Classic Transmission for less than $50 shipped.
Thread Starter
Instructor
Joined: Jun 2021
Posts: 213
Likes: 45
From: Georgia
Hi all, wanted to complete this thread and thank you for the help.
The kickdown solenoid on the under the dash was the issue. I found some information on this forum on how to reset that solenoid, and followed the instructions to reset. Once I did this, not only did my kickdown function perfectly but my hood door for cold air worked perfectly as well.
Thank you.
-Eric
The kickdown solenoid on the under the dash was the issue. I found some information on this forum on how to reset that solenoid, and followed the instructions to reset. Once I did this, not only did my kickdown function perfectly but my hood door for cold air worked perfectly as well.
Thank you.
-Eric
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