Mazda CX-7 2007 Workshop Manual page 1140

STEP
3 INSPECT FOR DTC IN PCM
• Inspect for DTCs related to the PCM on-
board diagnostic system.
• Are any DTCs displayed?
4 CONFIRM DTC U0073, U0516 USING M-MDS
• Retrieve DTC from EATC and HEC.
• DTCs (U0073, U0516) retrieved?
5 INSPECT TO SEE WHETHER MALFUNCTION
IS IN PCM OR ELSEWHERE
• Does cool air blow out when terminal 1AU of
PCM connector (A/C signal) is grounded?
6* INSPECT TO SEE WHETHER MALFUNCTION
IS IN A/C SIGNAL CIRCUIT (BETWEEN
REFRIGERANT PRESSURE SWITCH AND
PCM) OR ELSEWHERE
• Test voltage at following terminal of
refrigerant pressure switch.
— Terminal B (A/C signal)
• Is voltage approx. 12 V?
7* 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?
8 INSPECT TO SEE WHETHER MALFUNCTION
IS IN REFRIGERANT PRESSURE SWITCH,
REFRIGERANT AMOUNT, OR ELSEWHERE
• Does cool air blow out when terminals A and
B of refrigerant pressure switch connector
are shorted?
9* INSPECT TO SEE WHETHER MALFUNCTION
IS IN WIRING HARNESS (BETWEEN
REFRIGERANT PRESSURE SWITCH AND
PCM) OR ELSEWHERE
• Test voltage at following terminal of PCM.
— Terminal 1AU (A/C signal)
• Is voltage approx. 12 V?
10 INSPECT TO SEE WHETHER MALFUNCTION
IS IN REFRIGERANT PRESSURE SWITCH OR
REFRIGERANT AMOUNT
• Inspect refrigerant pressure switch.
• Is it okay?
11 INSPECT TO SEE WHETHER MALFUNCTION
(LACK OF CONTINUITY) IS IN A/C CONTROL
SIGNAL CIRCUIT (BETWEEN A/C RELAY
AND PCM) OR ELSEWHERE
• Does cool air blow out when terminal E of A/
C relay connector (A/C control signal) is
grounded?
12* INSPECT TO SEE WHETHER MALFUNCTION
(LACK OF CONTINUITY) IS IN PCM OR
WIRING HARNESS (BETWEEN A/C RELAY
AND PCM)
• Test voltage at the A/C relay control signal
terminal of PCM.
• Is voltage approx. 12 V?
13* INSPECT TO SEE WHETHER MALFUNCTION
IS IN MAGNETIC CLUTCH OR ELSEWHERE
• Test voltage at the following terminal of
magnetic clutch thermal protector.
— Terminal A (magnetic clutch operation
signal)
• Is voltage approx. 12 V?
07-03–16
2007 Mazda CX-7 Workshop Manual (1871–1U–06B)
SYMPTOM TROUBLESHOOTING
INSPECTION
Yes Go to appropriate inspection procedure.
No (Auto A/C)
Go to the next step.
(Manual A/C)
Go to Step 5.
Yes Network communication, for related system is malfunction.
Go to appropriate inspection procedure.
No Go to Step 6.
Yes Inspect and/or replace the PCM, then go to Step 18.
No Release short, then go to the next step.
Yes Go to Step 8.
No Go to the next step.
Yes Repair wiring harness between PCM and refrigerant
pressure switch, then go to Step 18.
No Inspect PCM, then go to Step 18.
Yes Go to Step 10.
No (Auto A/C)
Go to Step 11.
(Manual A/C)
Go to the next step.
Yes Go to Step 11.
No Repair wiring harness between refrigerant pressure switch
and PCM, then go to Step 18.
Yes If refrigerant amount is empty, replace condenser, vacuum
refrigerant line more than 30 min by vacuum pump, and
add refrigerant to specified level, then go to Step 18.
No Replace refrigerant pressure switch, then go to Step 18.
Yes Release short, then go to the next step.
No Go to Step 13.
Yes Inspect PCM, then go to Step 18.
No Repair wiring harness between A/C relay and PCM, then go
to Step 18.
Yes Inspect magnetic clutch, then go to Step 18.
No Go to the next step.
Revised 8/2006 (Ref. No. R087/06)
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