Solving Cadillac Seville A/C Heater Control Problems
It's the middle of winter, you're in your Cadillac Seville and your heater isn't working. This is one of the worst situations a driver can be in. Even after pushing all the buttons and turning all the knobs of the A/C heater control, it just doesn't seem to work. Here's quick guide to help you diagnose Cadillac Seville A/C Heater Control problems.
The air blown out of the vent isn't hot.
A number of problems may cause this to happen. The first two causes and the simplest ones to fix are either a blown fuse or a malfunctioning relay. A simple swap of these components is all it will take to handle the problem. Another problem is a stuck thermostat that is tricky to fix but relatively easier to replace. Blockage in the cut-off valve of the vacuum actuated heater may prevent engine heated water from getting into the passenger compartment, where it transfers its heat.
The heater does not turn on.
This problem usually occurs because of a problem in the Cadillac Seville's electrical system. If you're lucky, a blown fuse is the only thing you have to worry about. Worse, the control module of the heater has died and will need to be replaced. Worst, you may have a damaged wire somewhere along the airconditioning and the heater control system. Looking for the damaged wire will be a time-consuming process.
The heater control seems to turn on but there is no air coming out of the vents.
One very likely cause of this problem is a bad blower motor. Blower motors usually last a long time and don't need regular maintenance, but that still won't stop them from suddenly dying one day. Another cause is a bad motor relay, and as usual, a quick replacement will have the air rushing out of the vents in no time.
The air temperature does not match the setting on the heater control.
This problem is caused by one of many things. Firstly, there is a chance that the heater control itself is malfunctioning, a likely occurrence if it is already old or has been battered. If you've just replaced the control, you've either been given a lemon or you may have another problem. Second problem is a malfunctioning temperature sensor, also a product of aging and wearing out. Replace the part as usual. Lastly, you may have a bad air door control motor. It is possible to fix this component. If you've no success in doing so, replace as always.