Mazda MX-5 1990 Workshop Manual page 753

u
U-10
TROUBLESHOOTING GUIDE·
05UOUX-014
05UOUX-015
Step 4
1. Disconnect the magnetic clutch connector.
2. Check for continuity between the magnetic clutch connec-
tor and a body ground.
Note
• Set the ohmmeter to x1,000 range.
3. If there is no continuity, replace the magnetic clutch.
4. If there is continuity, adjust the magnetic clutch clearance
or check the compressor for internal trouble.
Step 5
1. Start the engine.
2. Turn the blower and
Ale
switches ON.
3. Measure the voltage at the following terminal-wires of the
AIC relay connector.
Wire Voltage Action
(B/L)
12V Go to Step 6
OV Next, check wire (LlY)
(L/Y) 12V Next. check wire (L/G)
OV
Repair wire (LlG)
(AD FAN 20A fuse-Ale relay)
(L) 12V Next, check wire (L/B)
OV
Repair wire (L/G)
(WIPER 20A fuse-A/C relay)
(L/B) 12V
Check ECU terminal voltage
OV Replace A/C relay
Step 6
1. Disconnect the refrigerant pressure switch connector.
2. Check continuity of the refrigerant pressure switch.
Continuity Action
Yes Repair wiring harness
(Ale relay-Refrigerant pressure switch-Magnetic clutch)
No Go to Step 7
Step 7
1. Measure the refrigerant pressure. (Refer to page U-31.)
Normal pressure
Low-pressure side:
147-294 kPa (1.5-3.0 kg/cm2, 21-43 psi)
High-pressure side:
1,177-1,619 kPa (12.0-16.5 kg/cm2, 171-235 psi)
2. If not as specified, check the refrigerant system by refer-
ring to the troubleshooting information on page U-12.
3. If correct, replace the refrigerant pressure switch.