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Electronic Climate Control

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Old Jan 6, 2026 | 07:12 PM
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Default Electronic Climate Control

Hi all. I have a 89 convertible and I’m not sure if I have an electronic climate control problem or a blend door issue. If the temperature is set at 60 it blows cold air but if I put it at 70 it’s like it’s on 90 and blows very hot air and won’t go back to 60. Anyone have any ideas? Thanks in advance
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Old Jan 10, 2026 | 04:11 PM
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What's the actual temperature in the car at the time?

Setting target temperature to maximum or minimum forces the control to ignore the temperature and do max heating or max cooling. One degree off, it's back to responding to actual temperature.

"Won't go back to 60", as in the controls will not reduce the target temperature back to 60?
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Old Jan 11, 2026 | 12:28 AM
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Originally Posted by FCiolino
Hi all. I have a 89 convertible and I’m not sure if I have an electronic climate control problem or a blend door issue. If the temperature is set at 60 it blows cold air but if I put it at 70 it’s like it’s on 90 and blows very hot air and won’t go back to 60. Anyone have any ideas? Thanks in advance
I just did my heater core today. So there is a clip on the actuator for the blend door that is prone to breakage. It could also be light corrosion on the connector to the wiring harness to this actuator - this is low voltage and sometimes even a thin film of corrosion is enough to cause sporadic behavior or failures altogether.

So, to clarify do you mean the actual temperature won't go back down or the display won't let you set the temperature lower? I may have the latter situation myself.
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Old Jan 11, 2026 | 04:49 AM
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Default Electronic Climate Control

The temperature will not come down. The display seems to be working fine but I was wondering if it just wasn’t sending the signal to the blend door actuator. Can you reach the connector at the blend door without taking the dash apart?
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Old Jan 11, 2026 | 08:38 AM
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You can access the blend door motor after removing passenger side panel that has the courtesy light.
The ecm was unbolted and slid out to get this view.


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Old Jan 11, 2026 | 12:14 PM
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Originally Posted by FCiolino
The temperature will not come down. The display seems to be working fine but I was wondering if it just wasn’t sending the signal to the blend door actuator. Can you reach the connector at the blend door without taking the dash apart?
It's possible it's an electrical problem but the most likely scenario is that the clip holding the blend door rod has become disconnected or broken. If it is broken there is a Dorman clip kit (75450), and the black clip will work on the setup.

Also clean up your electrical contacts on the connector while you're in there. Mine had an aftermarket stereo wiring jumbled in there so I had to remove quite a bit to access. It would be a tight fit with the ECM still bolted in there but Agent did it.
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Old Jan 12, 2026 | 09:31 AM
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Thank you so much. I’m going to try to get in there as soon as I can.
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