Heater Control - Unable to Adjust Air Temperature

88mazda01

Category Applicable Model/s Subject Bulletin No. 059/88
15 (See Below) HEATER CONTROL Issued 2/19/88
(LOGICON) Revised
DESCRIPTION

There is a possibility that the heater control (logicon) may become unable to adjust the air temperature on 1988 MX-6 GT, 1986-88 RX-7 and 1988 RX-7 convertible vehicles produced prior to September, 1987.

This may be caused by damage in the heater control (logicon) circuit. This damage is due to the surge current generated in the air-mix door motor drive circuit.

If you encounter a complaint such as warm air blowing from the air vents even when the A/C is operating at the coldest position, please carry out the following inspection procedure.

If necessary, please replace the heater control with a modified one listed on the next page.



INSPECTION PROCEDURE

1. Warm up the engine completely.

2. Turn on the blower fan switch. Set the air flow at vent mode. Turn on the air conditioner if equipped. Adjust temperature control lever to the warmest position.

3. If warm air is blowing, go to step 4.

If cold air is blowing, inspect the heater control amp as per Service Bulletin (Cat.15, No .037/86), airmix motor, related wire harness, heater unit, and operating link, as per Service Bulletin (Cat.15, No.056/88).

4. Set the temperature control lever at the coldest position. If warm air is blowing from the vents, replace the heater control with a modified one. Confirm the correct operation of heater and air conditioner system.



VIN OF PRODUCTION CHANGE



PARTS INFORMATION



NOTE:
As well as the new (modified) part, the former (old) part produced on and after August 20, 1987 can be used as a repair part. These good parts can be identified as mentioned below.