heater control

2000 jimmy, A/C system seems to work well, but there is no hot air. Coolant is circulating fine, and heater core is not plugged. I think the problem is electrical. The speed control, for the blower, fails to change the speed.

How do you know the heater core is fine?

Where does your temperature go when the engine is completely warmed up?

well both the inlet and outlet hoses are warm at normal eng. temp. Engine also comes up to temp, and is maintained. there are no leaks on the cooling system.

Ok, I had the opposite problem. First, no heat because core needed purging. Then, no way to stop the heat, as there was no control of the temperature. That turned out to be the contol panel, $400 later! Mine is the ECC version, way more things to go wrong than the standard edition.

well both the inlet and outlet hoses are warm at normal eng. temp. Engine also comes up to temp, and is maintained. there are no leaks on the cooling system.

Stop being so general.

WHERE does the needle go up on the temp gauge when the engine has been run for awhile?