93 Heater Control Malfunction

[dbrannon79]

Anyone have experience with the 93-94 digital heater controls? recently my hot cold control had gone haywire. I thought I had it fixed messing with the actuator motor, but it's acting up again. tried to move the control from cold to hot and after a couple of seconds the screen just starts flashing at me with no change in vent temps. not sure how to diagnose if the actuator motor is bad or if the 32 year digital control has gone fubar!

 

[MrMarty51]

Anyone have experience with the 93-94 digital heater controls? recently my hot cold control had gone haywire. I thought I had it fixed messing with the actuator motor, but it's acting up again. tried to move the control from cold to hot and after a couple of seconds the screen just starts flashing at me with no change in vent temps. not sure how to diagnose if the actuator motor is bad or if the 32 year digital control has gone fubar!

I used to have a spare on the shelf but it gone. Must have give it to someone in needy.
I robbed it frum a cash fir clunkers truck in the scrapping yard.

 

[dbrannon79]

I was considering gallivanting out to the pick a part yard for one of the controls this week and maybe even another actuator motor. might even take my cordless drill battery or a jump pack and test it in the yard before removing from a donor rig! I need to see what they want for them, last time I was out there, they had started charging for any little piece!

 

[dbrannon79]

it would be nice if there was a simple way to convert it to mechanical controls like the square bodies were. the less digitalis the better LOL

 

[dbrannon79]

I found a new blend actuator motor on the jungle site for $20 I can get here tomorrow. Ordered that since the JY charges about the same for them and from what I've read online that is the most common issue. if that doesn't fix it, then I will know it's the digital control in the dash. New from the auto parts is $60 for this blend motor.

I didn't want to sink $60 in to it just to find out it's not the issue. the other day when it was doing this, I pulled this motor out of the dash and it seemed fine, no cracked gears and would function while in my hand so I put it back into the dash.

 

[WarWagon]

and from what I've read online that is the most common issue.

I agree. My buddy's 1993 did the flash thing and it was a mode door actuator. Check all of the actuators before looking at the control head. Rec, mode, hot/cold.

You could find the "bad actuator" by selecting a mode to match where it was stuck. Then it wouldn't flash on key on if you were fast enough. YMMV

No, no thanks on the vac powered square body krap! Just got done with that obsolete carryover krap on a 2020 GM van that ate control heads due to vacuum leaks that were hissing bad. Unreal that GM's using vac controls in the 2020's!

 

[dbrannon79]

Well I'm back in business!! had to take a break from playing with injectors to install the blend motor, even ordered some replacement LED bulbs for the display since they were all burned out. tested all functions, heat and AC are working now YAY!

Took a pic but my phone's camera flash doesn't show the new lights too well. at least now I can see the buttons in the dark LOL

 

[Will L.]

I found a new blend actuator motor on the jungle site for $20 I can get here tomorrow. Ordered that since the JY charges about the same for them and from what I've read online that is the most common issue. if that doesn't fix it, then I will know it's the digital control in the dash. New from the auto parts is $60 for this blend motor.

I didn't want to sink $60 in to it just to find out it's not the issue. the other day when it was doing this, I pulled this motor out of the dash and it seemed fine, no cracked gears and would function while in my hand so I put it back into the dash.

Can you share the link? Might help others, including me. 95 hummers use the same one. Looks good.

 

[dbrannon79]

Here is the blend door motor

https://www.amazon.com/dp/B07DLPR6TM

and the LED lights I used in the control. it's a pack of 10 but there is only 3 in the control. they do have a polairty so it's a trial n error to get them in the right orientation. this is for the back lit buttons. the actual display light is not replaceable.

https://www.amazon.com/dp/B0D1JSJF2L

 

[Will L.]

Awesome, thanks.
The same bulbs are used in Hummer gauges. Hmmm

Thanks should help in the future!

 

[dbrannon79]

From what I could tell, these are T4 or T4.5 bulbs.