TROUBLESHOOTING THE M998 ELECT SYST. - OD1617 - LESSON 1/TASK 1
d.
Lighting System.
While reading through these paragraphs
concerning troubleshooting the lighting system, refer to figure 4 on
the following page.
Malfunction:
LAMPS WILL NOT LIGHT.
Step 1. Begin by positioning the light switch to the circuit being
tested.
Now check for battery voltage at the sockets.
If battery
voltage is present, replace the bulb with a bulb known to operate.
If the bulb does not light, check for corroded connections, loose
lamp sockets, or damaged wire terminals.
Repair or replace any
damaged components.
Step 2.
Disconnect
the body wiring harness from the light switch.
Using a multimeter,
check for battery voltage at terminal F in the
body wiring harness.
If battery voltage is not present, repair the
body wiring harness,
following the procedures found in paragraph 4-62
of the TM.
If the
wiring harness cannot be repaired, notify IDS
maintenance.
Step 3. Working from the circuit chart (table 1 on page 19), connect
a jumper wire from terminal F to the terminal of the circuit being
tested.
If the lamps light with the jumper wire connected, replace
the main light switch, using the procedures contained in paragraph 4-
45 of the TM. If the lamps do not light, repair or replace the hood
wiring harness, or replace the body wiring harness, as appropriate,
following the procedures found in paragraphs 4-61 and 4-62 of the TM.
If the wiring harness cannot be repaired, notify IDS maintenance.
e.
Indicator, Gage, and Warning System.
While reading through
these paragraphs concerning troubleshooting malfunctions within this
system, refer to figure 5 on the following page.
Malfunction:
COOLANT TEMPERATURE GAGE INOPERATIVE.
Step 1.
Disconnect lead 33B from the coolant temperature sending
unit.
Turn the rotary switch to the RUN position.
The coolant
temperature gage should read the minimum temperature. Touch lead 33B
to ground; the coolant temperature gage should read the maximum
temperature.
If the coolant temperature gage operates properly,
replace
the
coolant
temperature
sending
unit,
following
the
procedures contained in paragraph 4-24 of the TM.
17
Previous Page
