GMC 1986 P-Truck Service Manual page 245

3B4-6 STEERING COLUMN
DIAGNOSIS OF THE STEERING COLUMN (CONT.)
PROBLEM
Turn Signal W ill Not
Stay In Turn Position
Hazard Switch
Cannot Be Turned
Off
Hazard Switch W ill
Not Stay On Or
D ifficu lt To Turn Off
No Turn Signal
Lights
Turn Indicator Lights
On, But Not Flashing
Front Or Rear Turn
Signal Lights Are
Not Flashing
POSSIBLE CAUSE
1. Foreign material or loose parts im­
pending movement of the yoke.
2. Broken or missing detent or cancelling
springs.
3. None of the above.
Foreign material between hazard sup­
port cancelling leg and yoke.
1. Loose switch, mounting screws.
2. Interference with other components.
3. Foreign material.
4. None of the above.
1. Faulty or blown fuse.
2. Inoperative turn signal flasher.
3. Loose chassis to column connector.
4. Disconnect column to chassis connec­
tor. Connect new switch to chassis and
operate switch by hand. If vehicle
lights now operate normally, signal
switch is inoperative.
5. If vehicle lights do not operate, check
chassis wiring for opens, grounds, etc.
1. Inoperative turn flasher.
2. Loose chassis to column connection.
3. Inoperative turn signal switch.
4. To determine if turn signal switch is
faulty, substitute a new switch into the
circuit and operate the switch by hand.
If the vehicle's lights operate normally,
the signal switch is inoperative.
5. If the vehicle's lights do not operate,
check light sockets for high resistance
connections, the chassis wiring for
opens, grounds, etc.
1. Burned out fuse.
2. Burned out or damaged turn signal
bulb.
3. High resistance connection to ground
at the bulb socket.
4. Loose chassis to column connector.
CORRECTION
1. Remove material and/or parts.
2. Replace the spring.
3. Replace the switch.
Remove the foreign material.
• No foreign material. Replace the
turn signal switch.
1. Tighten mounting screws to 2.8 N.m
(25 in. lbs.).
2. Remove the interference.
3. Remove the foreign material.
4. Replace the switch.
1. Replace fuse and check operation.
2. Replace the turn signal flasher.
3. Connect securely, check operation.
4. Replace the signal switch.
5. Repair the chassis wiring.
1. Replace the turn flasher.
2. Connect securely and check opera­
tion.
3. Replace the turn signal switch.
4. Replace the signal switch.
5. Repair the chassis wiring.
1. Replace fuse and check operation.
2. Replace the bulb.
3. Remove or repair the faulty connec­
tion and check operation.
4. Connect securely and check opera­
tion.