System Operates With Outside Air or Max. Cooling Capacity Only

COMPLAINT:
System operating with outside air or max. cooling capacity only (no heating capacity), except with temperature dial engaged in "MAX".

Cause/Remedy:
a) Short in in-car or temperature sensor for heat exchanger or their supply lines.

Check electric lines, eliminate short, renew temperature sensor, if required.

b) Short in temperature dial.
Renew temperature dial or eliminate short in supply line.
Perform final ground connection test.

c) Electronic switching unit for temperature control (9) defective. Renew electronic switching unit for temperature control, if required.