Dodge 2001 Ram 1500 Owner's Manual page 727

8R - 4 WIPERS/WASHERS
WIPERS/WASHERS (Continued)
However, these tests may not prove conclusive in the
diagnosis of this system on models equipped with a
high-line or premium Central Timer Module (CTM).
In order to obtain conclusive testing of the wiper sys-
tem on models with a high-line or premium CTM, the
Chrysler Collision Detection (CCD) data bus network
and all of the electronic modules that provide inputs
to or receive outputs from the wiper system compo-
nents must be checked. The most reliable, efficient,
and accurate means to diagnose the wiper system on
models with a high-line or premium CTM requires
the use of a DRBIII scan tool. Refer to the appro-
priate diagnostic information. The DRBIII scan tool
can provide confirmation that the CCD data bus is
functional, that all of the electronic modules are
sending and receiving the proper messages on the
CCD data bus, and that the wiper relay is being sent
the proper hard wired outputs by the CTM for it to
perform its wiper system functions.
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Check the fused ignition switch output (run-
acc) fuse (Fuse 6 - 25 ampere) in the Junction Block
(JB). If OK, go to Step 2. If not OK, repair the
shorted circuit or component as required and replace
the faulty fuse.
(2) Turn the ignition switch to the On position.
Check for battery voltage at the fused ignition switch
output (run-acc) fuse (Fuse 6 - 25 ampere) in the JB.
If OK, go to Step 3. If not OK, repair the open fused
ignition switch output (run-acc) circuit between the
JB and the ignition switch as required.
(3) Turn the ignition switch to the Off position.
Disconnect and isolate the battery negative cable.
Disconnect the instrument panel wire harness con-
nector for the multi-function switch from the switch
connector receptacle. Reconnect the battery negative
cable. Turn the ignition switch to the On position.
Check for battery voltage at the fused ignition switch
output (run-acc) circuit cavity of the instrument
panel wire harness connector for the multi-function
switch. If OK, go to Step 4. If not OK, repair the
open fused ignition switch output circuit between the
multi-function switch and the JB as required.
(4) If the problem being diagnosed involves only
the intermittent wipe feature, go to Step 5. If the
problem being diagnosed involves all wiper modes, or
only the Low and/or High speed modes, go to Step 7.
(5) Turn the ignition switch to the Off position.
Disconnect and isolate the battery negative cable.
Disconnect the instrument panel wire harness con-
nector (Connector C1) for the Central Timer Module
(CTM) from the CTM connector receptacle. Check for
continuity between the wiper switch mode sense cir-
cuit cavities of the instrument panel wire harness
connector for the multi-function switch and the
instrument panel wire harness connector (Connector
C1) for the CTM. There should be continuity. If OK,
go to Step 6. If not OK, repair the open wiper switch
mode sense circuit between the multi-function switch
and the CTM as required.
(6) Check for continuity between the wiper switch
mode signal circuit cavities of the instrument panel
wire harness connector for the multi-function switch
and the instrument panel wire harness connector
(Connector C1) for the CTM. There should be conti-
nuity. If OK, proceed to the diagnosis for the wiper
relay. (Refer to 8 - ELECTRICAL/WIPERS/WASH-
ERS/WIPER RELAY - DIAGNOSIS AND TESTING).
If not OK, repair the open wiper switch mode signal
circuit between the multi-function switch and the
CTM as required.
(7) Check for continuity between the two wiper
switch low speed output circuit cavities of the instru-
ment panel wire harness connector for the multi-
function switch. There should be continuity. If OK, go
to Step 8. If not OK, repair the open wiper switch
low speed output circuit between the two cavities of
the instrument panel wire harness connector for the
multi-function switch as required.
(8) Test the multi-function
(Refer to 8 - ELECTRICAL/LAMPS/LIGHTING -
EXTERIOR/MULTI-FUNCTION SWITCH - DIAG-
NOSIS AND TESTING). If the multi-function switch
tests OK, reconnect the instrument panel wire har-
ness connector for the multi-function switch to the
switch connector receptacle and go to Step 9. If not
OK, replace the faulty multi-function switch and test
the wiper system operation again. If still not OK, go
to Step 9.
(9) Turn the ignition switch to the Off position.
Disconnect and isolate the battery negative cable.
Measure the resistance between the headlamp and
dash wire harness ground wire for the wiper motor
and a good ground. The meter should read zero
ohms. If OK, go to Step 10. If not OK, repair the
open ground circuit to ground (G100) as required.
BR/BE
switch continuity.