circuit.
ONE GAUGE NOT OPERATING PROPERLY
NOTE: For connector terminal identification and wiring diagrams,
see BODY CONTROL COMPUTER - INTRODUCTION article. Perform
VERIFICATION TEST VER-1A after each repair.
CAUTION: Always turn ignition switch to OFF position prior to
disconnecting or connecting any module connector.
1) Push and hold RESET button while cycling ignition key; ON-
OFF-ON. Instrument cluster self-test will start. If inoperative gauge
reached proper calibration point, go to next step. If inoperative
gauge did not reach proper calibration point, replace instrument
cluster.
2) Stop instrument cluster self-test. If problem is with
speedometer, go to next step. If problem is with oil pressure gauge,
go to step 5). If problem is with temperature gauge, go to step 14).
If problem is with fuel level gauge, go to appropriate SELF-
DIAGNOSTICS article in ENGINE PERFORMANCE section and review
powertrain symptoms. If problem is with volt gauge, go to step 16). If
problem is with tachometer, go to step 18).
3) Using scan tool, select BODY, SYSTEMS TESTS then PCM
MONITOR. If scan tool displays PCM ACTIVE ON BUS, go to next step. If
scan tool does not display PCM ACTIVE ON BUS, go to appropriate
VEHICLE COMMUNICATIONS article.
4) Raise and support all wheels. Start engine and place gear
selector in drive. Using scan tool, select MIC, MONITORS then CCD BUS
ENGINE INFO. Read VSS. If vehicle speed on scan tool matches
speedometer, see appropriate ANTI-LOCK BRAKE article. If vehicle speed
on scan tool does not match speedometer, replace instrument cluster
circuit board.
5) Turn ignition on. If CHECK GAUGES light illuminated, go to
next step. If CHECK GAUGES light did not illuminate, go to step 11).
6) Turn ignition off. Inspect oil level. If oil level is
within specification, go to next step. If oil level is not within
specification, adjust oil level and retest.
7) Turn ignition on. Disconnect engine Oil Pressure Switch
(OPS) connector. OPS is located near bottom of distributor. If CHECK
GAUGES light went out, go to next step. If CHECK GAUGES light did not
go out, go to step 10).
8) Remove OPS. Connect mechanical oil pressure gauge to OPS
port. Start engine. If engine oil pressure at idle is 4 psi or more,
go to next step. If engine oil pressure at idle is less than 4 psi,
repair mechanical engine problem.
9) Run engine to reach normal operating temperature. If
engine oil pressure at idle is 4 psi or more, replace OPS. If engine
oil pressure at idle is less than 4 psi, repair mechanical engine
problem.
10) Turn ignition off. Disconnect PCM White connector C2. PCM
is located in engine compartment on right inner fender. Using an
external ohmmeter, measure resistance between ground and PCM Black
connector terminal No. 23 (Gray/Orange wire). If resistance is less
than 5 ohms, repair short to ground in Gray/Orange wire. If resistance
is 5 ohms or more, replace PCM.
11) Disconnect engine Oil Pressure Switch (OPS) connector.
OPS is located near bottom of distributor. Using an external ohmmeter,
measure resistance between ground and OPS connector Black/Light Blue
wire. If resistance is less than 5 ohms, go to next step. If
resistance is 5 ohms or more, repair open Black/Light Blue wire.
Black/Light Blue wire is a common sensor ground. If no other engine
sensors are failed, repair ground between sensor and splice. If
Use Scan Tool To Verify VSS
Signal Is Sent By PCM
\b\
\
\
\
\b\
\
\
921 Not Receiving Distance Pulse Check PCM Software Level;
Message From PCM Use Scan Tool To Verify
Distance Pulse Message Is
Sent By PCM
\b\
\
\
\
\b\
\
\
940 Not Receiving Air Bag Light On Check CCD Bus Connections At
Message From Air Bag Module ACM; Check ACM Fuse
\b\
\
\
\
\b\
\
\
950 Not Receiving ABS Light On Message Check CCD Bus Connections
From Anti-lock Brake Control ModuleAt Anti-Lock Control Module;
Check Anti-Lock Control
Module Fuse
\b\
\
\
\
\b\
\
\
999 Undefined Error Record Failure Message;
Press RESET Button To
Continue Self-Diagnostic
Test
\
\
\
\
\
\
\
\f
2) If no DTCs appear, cluster will start a walking segment
test. First, all segments will be illuminated, then each segment in
sequence. If any segment does not illuminate, repeat test to confirm
and replace instrument cluster. When walking segment test is complete,
bulb check will start.
3) If any bulb does not light, remove instrument cluster and
check bulb and bulb holder. See INSTRUMENT CLUSTER under REMOVAL &
INSTALLATION. Ensure bulb holder is properly installed in cluster. If
bulb and bulb holder are okay, replace instrument cluster. If LED does
not light, replace instrument cluster. When bulb check is complete,
gauge actuator test will start.
4) Each gauge needle should stop at 3 calibration points,
then return to relaxed position. If any gauge does not perform as
specified, remove instrument cluster. See INSTRUMENT CLUSTER under
REMOVAL & INSTALLATION. Inspect all connections between printed
circuit board and gauge terminals, repair as necessary. If connections
are okay, replace instrument cluster. Instrument cluster will
automatically exit self-diagnostics when test is complete.
SYSTEM TESTS
NOTE: There are 2 instrument cluster connectors. These connectors
look identical. Identify connector by wire color. See WIRING
DIAGRAMS.
BRAKE WARNING LIGHT INOPERATIVE
1) Ensure parking brake is released. Turn ignition on. If
brake warning light stays on, check and repair hydraulic brake system
as necessary. See appropriate DISC & DRUM article in BRAKES section.
2) If brake warning light does not illuminate when ignition
is on, check fuse No. 17 (10-amp) on Ram Pickup or fuse No. 11 (10-
amp) on Ram Van and Ram Wagon in junction block. Junction block is
located at left end cover of instrument panel. If fuse is okay, go to
next step. If fuse is blown, locate and repair cause of blown fuse.
Install new fuse and recheck system operation.
3) Turn ignition on. Measure voltage between ground and power
side of fuse No. 17 on Ram Pickup or fuse No. 11 on Ram Van and Ram
Wagon. If battery voltage is present, go to next step. If battery
voltage is not present, locate and repair open circuit between to