On mine, it's the fourth relay from the inside out. In case they are in a different order, it should be the relay with two large wires and two small wires coming into it. One of the large wires is power and the other goes to the fan. One of the big wires should be purple with a black stripe. Spray WD-40 into the socket before plugging back in. This has been a BIG problem spot for GM. The wiring, not the relay, is what causes the problem. the contacts get hot and lose contact, then get hotter and quit working completely. I your connector looks burned, it may still work if you use the WD-40. The relay may still be good, too. This cost GM a lot of head gasket repairs due to stupid engineering and overheating. Typical GM.
Low coolant? Bad thermostat? Heater core air bound, restricted, or plugged? Water pump not circulating coolant? Temperature control switch not working?
No/low coolant, bad thermostat, dirty/plugged radiator (inside and/or outside of it), air pocket in coolant, electric fan relay, temp switch for fans, bad fans.
It is located on the left side of the engine between the 6th and 8th cylinder on the block.
It is on the driver side head, back by the last spark plug #5 cylinder.
There is a sensor that is in the overflow bottle that may be bad causing the "low coolant light" to illuminate. The coolant level switch is located on the bottom side of the coolant tank. The switch contains a reed switch and a magnetic float. When the coolant level is normal, the float rests away from the reed switch, causing the switch to be open. When the coolant level decreases in the coolant recovery tank below a specified level, the float rests on the reed switch and the switch closes, illuminating the LOW COOLANT light. The coolant level switch is a part of the coolant tank. If the switch needs to be replaced, the coolant tank must be replaced.
The switch is just across from the battery located in the rad reservor, to remove it and clean the sensor probe, you have to remove the battery.
Not plugged in.
No, if nothing is plugged in pulling current then you are using no electricity by leaving the switch in the on position.
brake switch out of adjustment, master cylinder comp port plugged, rear brake hose collaspsed or ebrake cables seized
Check coolant level Test and/or replace thermostat Make sure heater core is not plugged restricted, or air bound Make sure coolant is being circulated by water pump Check heater control switch and /or cable
Low coolant? Thermostat not closing allowing engine temperature to rise? Plugged heater core? Air bound heater core? Water pump not circulating coolant? Heater control cable not adjusted properly? Bad selector switch?
its called your heater core No it is called your heater control valve