Mazda RX-8 Workshop Manual page 2486

2 INSPECT A/C COMPRESSOR OPERATION
Start engine.
Turn A/C switch and fan switch
on.
Does A/C compressor operate?
3 INSPECT FOR DTC IN PCM AND HVAC
SYSTEM
Inspect for DTCs related to the
PCM and HVAC system on-board
diagnostic system.
Are any DTCs displayed?
4 INSPECT TO SEE WHETHER MALFUNCTION
IS IN A/C AMPLIFIER OR ELSEWHERE
Does cool air blow out when
terminal 1M of A/C amplifier
connector (24-pin, A/C signal) is
grounded by a jumper wire?
5* INSPECT TO SEE WHETHER MALFUNCTION
IS IN A/C SIGNAL CIRCUIT (BETWEEN
REFRIGERANT PRESSURE SWITCH AND
PCM) OR ELSEWHERE
Test voltage at the following
terminal of refrigerant pressure
switch:
Is voltage approx. 12 V?
6* INSPECT TO SEE WHETHER MALFUNCTION
(LACK OF CONTINUITY) IS IN WIRING
HARNESS (BETWEEN REFRIGERANT
PRESSURE SWITCH AND PCM) OR PCM
Test voltage at A/C signal terminal
of PCM.
Is voltage approx. 12 V?
Terminal B (A/C
signal)
and 2.
YesGo to Step 1 of troubleshooting index No.6.
No Go to next step.
YesGo to appropriate inspection procedure.
No Go to next step.
YesReplace A/C amplifier, then go to Step 17.
No Remove the jumper wire, then go to next step.
YesGo to Step 7.
No Go to next step.
YesRepair wiring harness between PCM and
refrigerant pressure switch, then go to Step
17.
No Inspect PCM, then go to Step 17. (See
INSPECTION [13B-MSP].)
PCM