
Lit. No. 28270, Rev. 00
July 1, 2005
69
TROUBLESHOOTING GUIDE
HEADLAMP TROUBLESHOOTING – SNOWPLOW DRL LAMPS*
Incorrect Operation or No DRL Lamps
* Snowplow DRLs operate as a series circuit and will illuminate bulb at 1/2 intensity. In some applications, the OEM DRLs will stay illuminated with snowplow attached.
BASIC CHECK QUESTIONS
SOLUTIONS
1
Fully understand OEM DRL operation
Refer to vehicle owner's manual for DRL operation.
2
OEM headlamps and DRLs operating correctly
OEM headlamps must be fully operational for correct Isolation Module operation.
3
OEM DRL fuse tests good
Refer to vehicle owner's manual for fuse location and size.
4
Harnesses connected at vehicle and snowplow (all)
Harnesses must be connected for all snowplow and headlamp functions.
5
Corrosion at harness connectors
Replace as needed.
6
Ignition on
Ignition must be "on" for snowplow DRL operatation.
7
Does control power up with key on
Go to
Control Test.
8
Snowplow headlamp and park/turn lamps all working correctly
See wiring diagram in this guide and
go to
Harness Tests.
9
Correct Isolation Module kit installed for application
Verify per Quick Match at www.westernplows.com.
10
Isolation Module and harnesses correctly installed per instructions Refer to Isolation Module instructions.
11
Harness wired per drawing
Refer to Electrical Schematics Guide.
12
Bulb burned out
Replace with proper bulb.