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Cadillac Repair/Heater not hot


It is not hot air coming out when heater is on.  The baffle is in the heater position (arm is counterclockwise).  I tested the hoses with a meat thermometer.  The top hose read 133.  Then I tested the bottom hose and it read 120.  Then retested the top hose and it read 126.  Can you advise.

Fellow Expert volunteer,


Hi Bob,

What temperature is the cooling system when engine is warm? You can't just use heater hose temps here, because engine heated coolant feeds into the core and back out. The heater control valve bypasses the heater for A/C. You should have a minimum of a 195 degree thermostat. I have a 160 in my Suburban for summer and put a 195 in it for winter.

Get back to me on the temps of the radiator, upper hose, lower hose.

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Rob Painter


Alarm system questions cannot be answered on this forum. These systems are not what I can answer. Without being physically at the vehicle and not knowing what kind of electrical service has been done on the vehicle, there is no possible way to give an accurate answer over the internet. My expertise is in Ignition/key based anti-theft systems. These issues include GM VATS (resistor chip in key blade) PASSLOCK (MRD)-ignition lock rotation based, no special ignition key and the PKIII Transponder (computer chip in key) systems. These systems are not alarm based and are integral with the starting of the engine. This is why I cannot diagnose alarm problems without physically looking at the vehicle: Alarm systems are a completely different annimal than ignition key/lock based anti-theft system. Many alarm questions come from vehicles 10 years old, and since older, many hands that had been involved over the years.I am an expert in all GM factory (ignition/key based)systems. Alarm system questions pose to many situations beyond my knowledge as to what has been done to the vehicle over the years. Some guy may have actually wired the stereo into the alarm system. Who knows? Over my past 30 years in vehicle wiring repair, I have seen unbelievable wiring disaters done by guys that consider themselves "mechanics." I have seen stereos and alarms intalled using surgical tape. I have seen modules burn up, un-fused circuits, wiring jambed between the doors and even lamp cord used for a starter kill. To answer alarm questions over the internet without examining the vehicle is like asking; What does it take to remove a dent?


Education/Credentials-ASE certified. 11 years with a GM dealer and 17 years with a repair facility dealing with only the repair of theft recovered vehicles.

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