Mazda MX-5 1990 Workshop Manual page 751

u
(L1G)(LIY)
U-8
TROUBLESHOOTING GUIDE
g--(LlR)
L1G) (L/R)
~(LlW)
(L1Y)
o5uoux-90
8
05UOUX-010
Step 3
1. Turn the ignition switch ON.
2. Turn the blower switch and
Ale
switch OFF.
3. Measure the voltage at the terminal-wires of the resistor as-
sembly.
Wire Voltage Action
(L/R) 12V Next, check wire (L/W)
(1-pin
OV Replace blower motor
connector)
(UW) 12V Next, check wire (UR)
OV Replace resistor assembly
(UR) 12V Next, check wire (UG)
(4-pin
OV Replace resistor assembly
connector)
(UG) 12V Next, check wire (UY)
OV Replace resistor assembly
(L/y)
12V Go to Step 4
OV Replace resistor assembly
Step 4
1. Turn the ignition switch· ON.
2. Turn the blower switch to the fourth position.
3. Measure the voltage at terminal-wire (8) of the blower switch
connector.
Wire
Voltage Action
(B)
OV Go to Step 5
12V Repair wire harness
(Blower switch-Body ground)
Step 5
1. Turn the ignition switch ON.
2. Turn the blower switch and
Ale
switch OFF.
3. Measure the voltage at the terminal-wires of the blower
switch connector.
Wire Voltage Action
(UW) OV Repair wire harness
(Resistor assembly-Blower switch)
12V Next, check wire (UR)
(UR) OV Repair wire harness
(Resistor assembly-Blower switch)
12V
Next, check wire (UG)
(UG)
OV Repair wire harness
(Resistor assembly-Blower switch)
12V Next, check wire (UY)
(UY) OV Repair wire harness
(Resistor assembly-Blower switch)
12V
Replace blower switch