GMC 1986 P-Truck Service Manual page 247

3B4-8 STEERING COLUMN
DIAGNOSIS OF THE STEERING COLUMN (CONT.)
PROBLEM
Hazard Signal Lights
W ill Not Flash—Turn
Signal Functions
Normally
Tone Alarm Does
Not Sound With Key
Fully Inserted In
Lock Cylinder With
D river's Door Open
10. Damaged or broken tone alarm switch.
11. Inoperative tone alarm switch (switch
12. Tone alarm switch contact gap is too
POSSIBLE CAUSE
1. Blown fuse.
2. Inoperative hazard warning flasher.
3. Loose chassis to column connection.
4. Disconnect column to chassis connec­
tor. Connect new switch into system
without removing old. Depress the
hazard warning button and observe
the hazard warning lights. If they now
work normally, the turn signal switch is
faulty.
5. If the lights do not flash, check wiring
harness " K" lead (brown) for open be­
tween hazard flasher and harmonica
connector. If open, fuse block is faulty.
1. Loose connection at the tone alarm.
2. Voltage not available to the tone alarm.
3. Faulty tone alarm.
4. Door jamb switch on the driver's side
is maladjusted or inoperative.
5. Short in the chassis wiring.
6. Short or fault in the signal switch wir­
ing.
7. Chips, burrs, foreign material is pre­
venting actuator tip function. NOTICE:
Key must be removed or the cylinder
in the " run" position before removing
the lock cylinder.
8. Faulty lock cylinder.
9. Chips, foreign material affecting the
tone alarm switch operation.
appears good but will not make the
tone alarm switch function check).
large
CORRECTION
1. Replace fuse and check operation.
2. Replace the hazard warning flasher.
3. Connect securely and check opera­
tion.
4. Replace the turn signal switch.
5. Replace fuse block. Refer to SEC. 8B
(CHASSIS ELECTRICAL) in this
manual.
1. Connect securely.
2. Check the continuity of the chassis
wiring and repair as required.
3. Replace the tone alarm.
4. Adjust or replace as required.
5. Check by separating chassis to col­
umn connector. Connect E and F fe­
male contacts on the chassis side
(bent paper clip will work). If tone
alarm sounds, continue diagnosis. If
not, locate and repair chassis wiring.
6. Connect male E and F contacts of
connector with the jumper. Check
buzzer switch pads with the ohmme-
ter. If contact is made, function is nor­
mal. If not, replace the signal switch.
7. Remove chips and burrs. Reassem­
ble and check.
8. With the lock cylinder out (refer to
" Notice" under step 7), fully insert
and remove the key. The actuator
should extend and retract smoothly.
Total expansion of tip should be
1.25 mm (0.050 inch). If not, replace
the lock cylinder.
9. Remove and clean as required—re­
assemble and check.
10. Replace the tone alarm switch.
11. Connect the ohmmeter leads to the
tone alarm switch probes. Press on
the actuator pad until the interior
points contact. If contact is not made,
replace the tone alarm switch.
12. Reset the contact gap.