Heater does not work on my 1996 jaguar xj6. AC works fine.

With regards to the heater...the XJ6 have a motor the moves hot water in to the car...driver side engine compartment. Occasionally it get stuck. Use a plastic hammer or anything heavy and tape on the motor lightly while the engine runs and with the heater on. Also the to make sure the relay is good. For AC make sure its charged. if you live in a cold area....the Freon leaks after each winter and needs to be recharged

A defective HVAC blower motor controller, or relay/micro switch in the control panel may cause the heater/AC blower motor not to work.

My 93 xj6 doesn't blow or anything but I found that if I kick the blower under the string wheel. It comes on. Then it's blowing cold on the dash and hot out the center counsel. Where do I kick to fix that? There are buttons that light up by the steering wheel. That look like the seat heater button. Is there a way to choose to make the thing blow cold in front and hot in back? 989-657-2563

MILES? CAN BE A PLUGGED HEATER CORE, HEATER CONTROL VALVE? ARE THE HEATER HOSES HOT GOING INTO THE FIREWALL??

may be the motor itself

cannot find blower relay

have you checked for hot water in the pipes ??

check your fuses and module that control those function on the vehicle

due to the fact there is duel zone heating in these cars there is a heater control unit could a amplifier these tend to fail and you wont be able to get any heat a genuine unit is very expensive around $1500 but if you shop around you can get one for around $250 non genuine
then its just a matter of getting a jag tech to fit it

good luck