2001 DODGE RAM fuel pressure

ENGINE CONTROL MODULE (DIESEL) - 50 WAY
CAV CIRCUIT FUNCTION
1 H104 18BR/OR IDLE VALIDATION SWITCH NO. 1
2 K244 20YL/DB CUMMINS BUS (+)
3 K6 18VT/WT 5V SUPPLY
4 K14 18BK/DB SENSOR GROUND
5 F18 18LG/BK FUSED IGNITION SWITCH OUTPUT (RUN-START)
6 G60 18GY/BK ENGINE OIL PRESSURE SENSOR SIGNAL
7 K21 18BK/RD INTAKE AIR TEMPERATURE SENSOR SIGNAL
8 G12 18GY/RD MANIFOLD AIR PRESSURE SENSOR SIGNAL
9- -
10 K7 18OR 5V SUPPLY
11 K104 18BK/LB SENSOR GROUND
12 K246 20YL/DG CUMMINS BUS (-)
13 K242 20WT DATA LINK (+) FUEL INJECTION PUMP
14 K2 18TN/BK ENGINE COOLANT TEMPERATURE SENSOR SIGNAL
15 K135 18YL/WT TRANSFER PUMP SUPPLY
16 H105 18LG/DB IDLE VALIDATION SWITCH NO. 2
17 K124 18GY CAMSHAFT POSITION SENSOR SIGNAL
18 K48 18DG FUEL INJECTION PUMP SYNC SIGNAL
19 - -
20 - -
21 K1 18DG/RD WATER IN FUEL SENSOR SIGNAL
22 V37 18RD/LG SPEED CONTROL SWITCH SIGNAL
23 K240 20BK DATA LINK (-) FUEL INJECTOR PUMP
24 V32 18YL/RD BRAKE SWITCH SENSE
25 H102 18LB/BK ACCELERATOR PEDAL POSITION SENSOR SIGNAL
26 G113 18OR PTO SWITCH SENSE
27 - -
28 K22 18OR/DB ACCELERATOR PEDAL POSITION SENSOR SIGNAL
29 S21 18YL/BK AIR INTAKE HEATER RELAY NO.1
30 Z12 18BK/TN GROUND
31 H101 18DB/WT ACCELERATOR PEDAL POSITION SENSOR SUPPLY
32 H103 18BK/YL ACCELERATOR PEDAL POSITION SENSOR GROUND
33 K45 18LB/RD FUEL SHUT-OFF SIGNAL
34 K44 18VT/OR LOW IDLE SELECT
35 K135 18YL/WT TRANSFER PUMP SUPPLY
36 K131 18BR/WT FUEL INJECTOR PUMP RELAY CONTROL
37 G85 18OR/BK WAIT-TO-START WARNING INDICATOR DRIVER
38 D21 18PK/DB SCI TRANSMIT
39 D20 18DG SCI RECEIVE
40 D2 18WT/BK CCD BUS (-)
41 D1 18VT/BR CCD BUS (+)
42 K247 20DB CUMMINS BUS SHIELD
43 G7 18WT/OR VEHICLE SPEED SENSOR SIGNAL
44 K243 20OR/BR DATA LINK SHIELD FUEL INJECTOR PUMP
45 K24 18GY/BK CRANKSHAFT POSITION SENSOR SIGNAL
46 - -
47 S22 18OR/BK AIR INTAKE HEATER RELAY CONTROL NO. 2
48 A14 18RD/WT FUSED B(+)
49 Z12 18BK/TN GROUND
50 A14 18RD/WT FUSED B(+)
8W - 80 - 40 8W-80 CONNECTOR PIN-OUTSBR/BE

POWERTRAIN CONTROL MODULE C2 (DIESEL) - BLACK 32 WAY
CAV CIRCUIT FUNCTION
9- -
10 K20 18DG GENERATOR FIELD
11 K54 18OR/BK (A/T) TORQUE CONVERTER CLUTCH SOLENOID CONTROL
12 - -
13 - -
14 - -
15 - -
16 - -
17 - -
18 - --
19 - -
20 - -
21 T60 18BR (A/T) 3-4 SHIFT SOLENOID CONTROL
22 - -
23 - -
24 - -
25 T13 18DB/BK OUTPUT SPEED SENSOR GROUND
26 - -
27 G7 18WT/OR (A/T) VEHICLE SPEED SENSOR SIGNAL
28 T14 18LG/BK OUTPUT SPEED SENSOR SIGNAL
29 T25 18LG/WT (A/T) GOVERNOR PRESSURE SENSOR SIGNAL
30 K30 18PK (A/T) TRANSMISSION CONTROL RELAY CONTROL
31 K7 18OR (A/T) 5V SUPPLY
32 - -
POWERTRAIN CONTROL MODULE C2 (GAS) - BLACK 32 WAY
CAV CIRCUIT FUNCTION
1 T54 18VT (A/T) TRANSMISSION TEMPERATURE SENSOR SIGNAL
2 K26 18VT/TN (5.2L/5.9L/8.0L) FUEL INJECTOR NO. 7 DRIVER
3 K115 18TN/BK (8.0L) FUEL INJECTOR NO. 9 DRIVER
4 K11 18WT/DB FUEL INJECTOR NO. 1 DRIVER
5 K13 18YL/WT FUEL INJECTOR NO. 3 DRIVER
6 K38 18GY FUEL INJECTOR NO. 5 DRIVER
7- -
8 K88 18VT/WT (A/T) GOVERNOR PRESSURE SOLENOID CONTROL
9- -
10 K20 18DG GENERATOR FIELD
11 K54 18OR/BK TORQUE CONVERTER CLUTCH SOLENOID CONTROL
12 K58 18BR/DB FUEL INJECTOR NO. 6 DRIVER
13 K28 18GY/LB (5.2L/5.9L/8.0L) FUEL INJECTOR NO. 8 DRIVER
14 K116 18WT (8.0L) FUEL INJECTOR NO. 10 DRIVER
15 K12 18TN FUEL INJECTOR NO. 2 DRIVER
16 K14 18LB/BR FUEL INJECTOR NO. 4 DRIVER
17 - -
18 - -
19 - -
20 - -
21 T60 18BR (A/T) 3-4 SHIFT SOLENOID CONTROL
22 - -
23 G60 18GY/OR ENGINE OIL PRESSURE SENSOR SIGNAL
24 - -
8W - 80 - 68 8W-80 CONNECTOR PIN-OUTSBR/BE

POWERTRAIN CONTROL MODULE C2 (GAS) - BLACK 32 WAY
CAV CIRCUIT FUNCTION
25 T13 18DB/BK (A/T) OUTPUT SPEED SENSOR GROUND
26 - -
27 G7 18WT/OR (A/T) VEHICLE SPEED SENSOR SIGNAL
28 T14 18LG/BK (A/T) OUTPUT SPEED SENSOR SIGNAL
29 T25 18LG/WT (A/T) GOVERNOR PRESSURE SENSOR SIGNAL
30 K30 18PK (A/T) TRANSMISSION CONTROL RELAY CONTROL
31 K7 18OR (A/T) 5V SUPPLY
32 - -
POWERTRAIN CONTROL MODULE C3 (DIESEL) - BLACK 32 WAY
CAV CIRCUIT FUNCTION
1 C13 18DB/OR A/C COMPRESSOR CLUTCH RELAY CONTROL
2- -
3 K51 18DB/YL AUTOMATIC SHUT DOWN RELAY CONTROL
4 V36 18TN/RD SPEED CONTROL VACUUM SOLENOID CONTROL
5 V35 18LG/RD SPEED CONTROL VENT SOLENOID CONTROL
6- -
7- -
8- -
9- -
10 - -
11 V32 18YL/RD SPEED CONTROL SUPPLY
12 A142 14DG/OR AUTOMATIC SHUT DOWN RELAY OUTPUT
13 T6 18OR/WT (A/T) OVERDRIVE OFF SWITCH SENSE
14 - -
15 K118 18PK/YL BATTERY TEMPERATURE SENSOR SIGNAL
16 - -
17 - -
18 - -
19 - -
20 - -
21 - -
22 C20 18BR A/C SWITCH SENSE
23 C90 18LG/WT A/C SELECT INPUT
24 V40 18WT/PK BRAKE SWITCH SENSE
25 T125 18DB GENERATOR SOURCE
26 K226 18DB/WT FUEL LEVEL SENSOR SIGNAL
27 D21 18PK/DB SCI TRANSMIT
28 D2 18WT/BK CCD BUS(-)
29 D220 18WT/VT SCI RECEIVE
30 D1 18VT/BR CCD BUS(+)
31 - -
32 V37 18RD/LG SPEED CONTROL SWITCH SIGNAL
BR/BE8W-80 CONNECTOR PIN-OUTS 8W - 80 - 69

Connector Name/Number Color Location Fig.
Cummins Bus (-) Left Front of Engine 10
Cup Holder Lamp Center of Instrument Panel 23,26
Data Link Connector BK Left Bottom of Instrument Panel 23,24
Day/Night Mirror BK Day/Night Mirror N/S
Daytime Running Lamp Module BK Left Fender Side Shield 14
Dome Lamp Rear of Cab 18
Driver Airbag BK Steering Wheel N/S
Driver Door Arm/Disarm Switch BK In Door 19
Driver Door Jamb Switch NAT Door Jamb 19
Driver Door Lock Motor BK In Door 19
Driver Door Window/Lock Switch BL In Door 19
Driver Heated Seat Module BL Under Seat N/S
Driver Heated Seat Switch RD Center of Instrument Panel N/S
Driver Lumbar Motor Under Seat N/S
Driver Power Seat Front Vertical Motor BK Under Seat N/S
Driver Power Seat Horizontal Motor BK Under Seat N/S
Driver Power Seat Rear Vertical Motor Under Seat N/S
Driver Power Seat Switch At Seat N/S
Driver Power Window Motor In Door 19
Duty Cycle EVAP/Purge Solenoid BK Right Fender Side Shield 17
Electric Brake Provision Bottom Left of Instrument Panel N/S
Engine Control Module (Diesel) Left Side Engine 12
Engine Coolant Temperature Sensor (Diesel) BK Left Front of Cylinder Head
(Diesel)10
Engine Coolant Temperature Sensor (Gas) BK On Thermostat Housing 3,6
Engine Oil Pressure Sensor (V6, V8) BK Near Distributor 3
Engine Oil Pressure Sensor (V10) Near Oil Filter 6
Engine Oil Pressure Sensor (Diesel) Left Side of Engine 12
Fuel Heater (Diesel) Left Side of Engine 10
Fuel Injection Pump (Diesel) Left Side of Engine, Below ECM 10
Fuel Injector No.1 BK At Fuel Injector 4,5
Fuel Injector No. 2 BK At Fuel Injector 4,5,6
Fuel Injector No. 3 BK At Fuel Injector 4,5,6
Fuel Injector No. 4 BK At Fuel Injector 4,5,6
Fuel Injector No. 5 BK At Fuel Injector 4,5,6
Fuel Injector No. 6 BK At Fuel Injector 4,5,6
Fuel Injector No. 7 BK At Fuel Injector 4,6
Fuel Injector No. 8 BK At Fuel Injector 4,6
Fuel Injector No. 9 BK At Fuel Injector 6
Fuel Injector No. 10 BK At Fuel Injector 6
Fuel Pump Module LTGY At Frame Rail 22
Fuel Transfer Pump (Diesel) Left Rear of Engine Bottom of
Pump10
BR/BE8W-90 CONNECTOR/GROUND LOCATIONS 8W - 90 - 3
CONNECTOR/GROUND LOCATIONS (Continued)

8W-95 SPLICE LOCATIONS
TABLE OF CONTENTS
page
SPLICE LOCATIONS
DESCRIPTION............................1
SPLICE LOCATIONS
DESCRIPTION
This section provides illustrations identifying the
general location of the splices in this vehicle. A spliceindex is provided. Use the wiring diagrams in each
section for splice number identification. Refer to the
index for proper splice number. For splices that are
not shown in the figures N/S appears in the Fig. col-
umn.
Splice Number Location Fig.
S100 Engine Harness Near T/O to Oil Pressure Sensor 3
S102 Headlamp and Dash Harness, Near T/O to Right Park/Turn Lamp 8
S103 Headlamp and Dash Harness, Near T/O to Left Park/Turn Lamp N/S
S104 Headlamp and Dash Harness, Near T/O to Left Front Headlamp N/S
S105 Headlamp and Dash Harness, In Power Distribution Center 7
S106 Headlamp and Dash Harness, In Power Distribution Center 7
S107 Headlamp and Dash Harness, Near Left Wheel Speed Sensor 7
S108 Headlamp and Dash Harness, Near Daytime Running Lamp Module 7
S109 Battery Harness, In T/O for Engine and Transmission Ground N/S
S110 Headlamp and Dash Harness, Near Left Wheel Speed Sensor 7
S111 Transmission Harness Near T/O to A/C Low Pressure Switch 2
S112 Headlamp and Dash Harness, Near Antilock Brake Controller 7
S113 Headlamp and Dash Harness, Near Antilock Brake Controller 7
S114 Headlamp and Dash Harness, In T/O to Chassis Harness 7
S116(V6, V8) Engine Harness, Near T/O to Fuel Injectors 1
S116 (V10) Engine Harness Rear of Engine 2, 4
S116 (Diesel) Transmission Harness, In T/O to Power Distribution Center 2
S117 (V6, V8) Engine Harness, Near T/O to Fuel Injectors 1
S117 (V10) Engine Harness, Near T/O to fuel Injector No. 8 1, 4
S118 (V6, V8) Engine Harness, Near T/O to Fuel Injectors 1
S118 (V10) Engine Harness, Rear of Engine 1, 4
S119 (V6, V8) Engine Harness, Near T/O to Fuel Injectors 1
S119 (V10) Engine Harness, Rear of Engine 1, 4
S120 (V6, V8) Engine Harness, Near T/O to Fuel Injectors 1
S120 (V10) Engine Harness, Rear of Engine 2, 4, 6
S120 (Diesel) Transmission Harness, Near T/O to A/C Low Pressure Switch 2
S121 (V6, V8) Engine Harness, Near T/O to Fuel Injector No. 5 3
S121 (V10) Engine Harness, Near T/O to Fuel Injector No. 7 4
S122 (V6, V8) Engine Harness, Top of Transmission 5
S122 (V10) Engine Harness, In T/O to Transmission N/S
S123 (V6, V8) Engine Harness, Near T/O to Fuel Injector No. 3 3
BR/BE8W-95 SPLICE LOCATIONS 8W - 95 - 1

Splice Number Location Fig.
S123 (V10) Engine Harness, Near T/O to Fuel Injector No. 3 4
S124 (V6, V8) Engine Harness, Top of Transmission 5
S124 (V10) Engine Harness, In T/O to Transmission N/S
S126 (V6, V8) Engine Harness, Near T/O to Fuel Injector No. 1 3
S126 (V10) Engine Harness, Near T/O to Engine Ground 4, 6
S126 (Diesel) Transmission Harness, Near T/O to Powertrain Control Module 2
S127 (V6, V8) Engine Harness, on Top of Transmission 6, 5
S127 (V10) Engine Harness, Near T/O to Transmission 6
S127 (Diesel) Transmission Harness, Near T/O to A/C Low Pressure Switch 2
S128 (Diesel) Transmission Harness, Near T/O to Power Distribution Center 2
S130(V6, V8) Engine Harness, Near T/O to Oil Pressure Sensor 3
S131 (V10) Engine Harness, Rear of Engine 4
S134 Fog Lamp Harness, In T/O to Right Fog Lamp N/S
S136 Fog Lamp Harness, In T/O to Right Fog Lamp N/S
S141 Headlamp and Dash Harness, Near T/O to Joint Connector No. 3 8
S143 Headlamp and Dash Harness, Near T/O to Power Distribution Center 7
S144 Headlamp and Dash Harness, Near T/O to Joint Connector No. 3 8
S160 (Diesel) Engine Harness, Near Fuel Transfer Pump N/S
S161 (Diesel) Transmission Harness, In T/O to Power Distribution Center 2
S164 (Diesel) Engine Harness, Near Fuel Transfer Pump N/S
S165 (Diesel) Engine Harness, Near Engine Control Module N/S
S166 (Diesel) Engine Harness, Near Engine Control Module N/S
S167 (Diesel) Engine Harness, Near Fuel Transfer Pump N/S
S168 (Diesel) Engine Harness, Near T/O to Engine Coolant Temoerature Sensor N/S
S170 (Diesel) Engine Harness, In T/O to Engine Control Module N/S
S171 Transmission Harness, In T/O to Power Distribution Cente 2
S172 (Diesel) Transmission Harness, Near T/O to A/C Low Pressure Switch 2
S173 (Diesel) Transmission Harness, Near T/O to A/C Low Pressure Switch 2
S174 (Diesel) Transmission Harness, In T/O to Power Distribution Center 2
S175 Transmission Harness, In T/O to Power Distribution Center 2
S176 Headlamp and Dash Harness, In Power Distribution Center 7
S177 Headlamp and Dash Harness, In T/O to Daytime Running Lamps Module 7
S179 Transmission Harness, In T/O to Power Distribution Center 2
S180 Headlamp and Dash Harness, Near Intake Air Heater Relay 8
S181 Headlamp and Dash Harness, Near Intake Air Heater Relay 8
S182 Headlamp and Dash Harness, In T/O to Daytime Running Lamps Module 7
S183 Headlamp and Dash Harness, In Power Distribution Center 7
S184 (Diesel) Engine Harnes, in T/O to Engine Control Module N/S
S202 Instrument Panel Harness, Near Overdrive Switch 12
S203 Instrument Panel Harness, Near Overdrive Switch 12
S204 instrument Panel Harness, In T/O to Cup Holder Lamp 12
S207 Instrument Panel Harness, Near Blower Motor 12
S209 Steering Wheel Harness, Near Remote Radio Switch N/S
S210 Steering Wheel Harness, Near Remote Radio Switch N/S
S300 Body Harness, Left Side Instrument Panel 10
8W - 95 - 2 8W-95 SPLICE LOCATIONSBR/BE
SPLICE LOCATIONS (Continued)

ENGINE 3.9L
DESCRIPTION
The 3.9 Liter (238 CID) six-cylinder engine is a
V-Type, lightweight, single cam, overhead valve
engine with hydraulic roller tappets. This engine is
designed to use unleaded fuel.
The engine lubrication system consists of a rotor
type oil pump and a full-flow oil filter.
The cylinders are numbered from front to rear; 1,
3, 5 on the left bank and 2, 4, 6 on the right bank.
The firing order is 1-6-5-4-3-2 (Fig. 1).
The engine serial number is stamped into a
machined pad located on the left front corner of the
cylinder block. When component part replacement is
necessary, use the engine type and serial number for
reference (Fig. 2).
DIAGNOSIS AND TESTINGÐENGINE
DIAGNOSIS - INTRODUCTION
Engine diagnosis is helpful in determining the
causes of malfunctions not detected and remedied by
routine maintenance.
These malfunctions may be classified as either
mechanical (e.g., a strange noise), or performance
(e.g., engine idles rough and stalls).
(Refer to 9 - ENGINE - DIAGNOSIS AND TEST-
ING - Preformance) or (Refer to 9 - ENGINE - DIAG-
NOSIS AND TESTING - Mechanical). Refer to 14 -
FUEL SYSTEM for fuel system diagnosis.
Additional tests and diagnostic procedures may be
necessary for specific engine malfunctions that can-
not be isolated with the Service Diagnosis charts.
Information concerning additional tests and diagno-
sis is provided within the following:
²Cylinder Compression Pressure Test
²Cylinder Combustion Pressure Leakage Test
²Cylinder Head Gasket Failure Diagnosis
²Intake Manifold Leakage Diagnosis
²Lash Adjuster (Tappet) Noise Diagnosis
²Engine Oil Leak Inspection
Fig. 1 Firing Order
Fig. 2 Engine Identification (Serial) Number
BR/BEENGINE 3.9L 9 - 3
ENGINE 3.9L (Continued)

DIAGNOSIS AND TESTINGÐPERFORMANCE
PERFORMANCE DIAGNOSIS CHARTÐGASOLINE ENGINES
CONDITION POSSIBLE CAUSES CORRECTION
ENGINE WILL NOT
CRANK1. Weak or dead battery 1. Charge/Replace Battery. (Refer to 8 -
ELECTRICAL/BATTERY SYSTEM/
BATTERY - STANDARD PROCEDURE).
Check charging system. (Refer to 8 -
ELECTRICAL/CHARGING - DIAGNOSIS
AND TESTING).
2. Corroded or loose battery
connections2. Clean/tighten suspect battery/starter
connections
3. Faulty starter or related circuit(s) 3. Check starting system. (Refer to 8 -
ELECTRICAL/STARTING - DIAGNOSIS
AND TESTING)
4. Seized accessory drive component 4. Remove accessory drive belt and
attempt to start engine. If engine starts,
repair/replace seized component.
5. Engine internal mechanical failure or
hydro-static lock5. Refer to (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)
ENGINE CRANKS BUT
WILL NOT START1. No spark 1. Check for spark. (Refer to 8 -
ELECTRICAL/IGNITION CONTROL -
DESCRIPTION)
2. No fuel 2. Perform fuel pressure test, and if
necessary, inspect fuel injector(s) and
driver circuits. (Refer to 14 - FUEL
SYSTEM/FUEL DELIVERY/FUEL PUMP
- DIAGNOSIS AND TESTING).
3. Low or no engine compression 3. Perform cylinder compression pressure
test. (Refer to 9 - ENGINE - DIAGNOSIS
AND TESTING).
ENGINE LOSS OF
POWER1. Worn or burned distributor rotor 1. Install new distributor rotor
2. Worn distributor shaft 2. Remove and repair distributor (Refer to
8 - ELECTRICAL/IGNITION CONTROL/
DISTRIBUTOR - REMOVAL).
3. Worn or incorrect gapped spark
plugs3. Clean plugs and set gap. (Refer to 8 -
ELECTRICAL/IGNITION CONTROL/
SPARK PLUG - CLEANING).
4. Dirt or water in fuel system 4. Clean system and replace fuel filter
5. Faulty fuel pump 5. Install new fuel pump
6. Incorrect valve timing 6. Correct valve timing
7. Blown cylinder head gasket 7. Install new cylinder head gasket
8. Low compression 8. Test cylinder compression (Refer to 9 -
ENGINE - DIAGNOSIS AND TESTING).
9. Burned, warped, or pitted valves 9. Install/Reface valves as necessary
10. Plugged or restricted exhaust
system10. Install new parts as necessary
9 - 4 ENGINE 3.9LBR/BE
ENGINE 3.9L (Continued)