Stoplights Do Not Operate (All). - Mazda MX-5 1990 Workshop Manual

LIGHTING SYSTEM
T
Troubleshooting
Symptom: Stoplights do not operate (all).
STOP 15A
FUSE
BOX
05UOTX-120
1CJt---(W/G)
(G)
05UOTX-121
STOPLl~ ~
~ ~
IJ
' HIGH-
Q~
MOUNT
~
STOPLIGHT
1/
05UOTX-122
05UOTX-119
Step 1
Check STOP 15A fuse in the fuse box.
If the fuse is burned, replace it. Check and repair the wire har-
ness, if necessary.
If the fuse is OK, go to Step 2.
Step 2
Measure the voltage at the following terminal-wires of the stop-
light switch connector.
Inspection
Wire Voltage Action
condition
12V
Next check wire (G)
Constant
(WIG)
OV
Repair wire
(WIG)
(STOP 15A fuse-Stoplight switch)
Brake pedal
(G)
12V Go to Step 3
depressed
OV
Check stoplight switch
Step 3
Check the stoplight bulbs.
If a bulb is burned replace it.
If the bulbs are OK, go to Step 4.
Step 4
Measure the voltage at the following terminal-wires of the right
and left stoplight connectors.
Inspection
Wire Voltage Action
condition
12V Next check wire (8)
(G)
OV
Repair wire (G)
Brake pedal
(Stoplight switch-Stoplight)
depressed
12V
Repair ground wire (8)
(B)
OV
Check for poor connection of con-
nectors
T-59