Daytime Running Lights (Drl) Do Not Operate - Mazda MX-5 1990 Workshop Manual

Wire
(L)
(B)
(R)
(W/R)
LIGHTING SYSTEM
T
Symptom; Daytime running lights (DRL) do not operate. (Turn signals function
normally.)
DRL operate with engine runing and following switches are off:
• Headlight switch
• Turn signal switch
• Hazard warning switch
• Parking brake switch (Parking brake released)
05UOTX-156
(G/Y) (8) (W/R)(L/Y)
(mill
Step 1
Connected to
WIPER 20A fuse
Ground
Parking brake switch
Headlight switch
HL
TNS
05UOTX-157
Warning
• Position the vehicle on a flat surface and block the
wheels to prevent vehicle movement.
1. Turn on the ignition switch.
2. Measure the voltage at the following terminal-wires of the
DRL unit.
3. If correct, replace the DRL unit.
Test condition Specification Action
Constant 12V
Repair wire (L)
(WIPER 20A-DRL unit)
Constant OV
Repair wire (B)
(ORL unit-Body ground)
Parki ng brake released 12V Go to Step 2
Headlight switch off
OV
Go to Step 3
05UOTX-159
05UOTX-160
05UOTX-158
Step 2
1. Disconnect the parking brake switch connector.
2. Check continuity between the terminal of the switch and a
body ground.
Parking brake lever
Continuity
Pulled one notch Yes
Released No
3. If not as specified, adjust or replace the parking brake switch.
4. If correct, repair wires (R) and (L/Y). (Parking brake switch
- DRL unit)
Step 3
1. Remove the column cover and disconnect the connectors
of the headlight switch.
2. Check continuity between the terminals of the headlight
switch connector.
Position
Terminal
BTN TNS
Headlight switch
ON
0
D
Headlight switch OFF
0---0:
Indicates continuity
3. If not as specified, replace the headlight switch.
4. If correct, repair wire
(W/R).
(Headlight switch - DRL unit)
T-79