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6E-44 Engine Control System (4JH1)
Lost Communication with The Engine Control Module (ECM)
Circuit Description
The engine control module (ECM), transmission control
module (TCM) and electronic hydraulic control unit
(EHCU) all communicate with the scan tool over the
Keyword 2000 serial data link. However, the ECM and
fuel injection pump control unit (PCU) communicates
with each other over the controller area network (CAN)
link. The CAN link is not used for communication with
the scan tool and is shared only between the ECM and
PCU.
Lost Communication with The Engine Control
Module (ECM)
Schematic Reference:
Engine Controls Schematics
Connector End View Reference:
Engine Controls
Connector End Views or Engine Control Module (ECM)
Connector End Views
Step Action
Value(s)
Yes
No
1
Did you perform the Diagnostic System Check-
Engine Controls?
Go to Step 2
Go to Diagnostic
System Check-
Engine Controls
2
Attempt to establish engine control module (ECM)
communications with the scan tool.
Does the ECM communicate with the scan tool?
Go to Intermittent
Conditions
Go to Step 3
3
Check the ECM C-56 and C-57 connectors for poor
connections.
Did you find and correct the condition?
Go to Step 17
Go to Step 4
4 Check
the
electronic hydraulic
control unit (EHCU)
C-67 connector for poor connection.
Did you find and correct the condition?
Go to Step 17
Go to Step 5
5
1. Turn ON the ignition, with the engine OFF.
2. Check the ECM (30A) (SFB-4), ECM (10A) fuse
(EB-4) and Engine (15A) fuse (C-6).Replace and
retest if open. If any fuse continues to open,
check for a short to ground on each circuit fed by
that fuse.
3. Turn OFF the ignition.
4. Disconnect the ECM C-56 harness connector.
5. Turn ON the ignition, with the engine OFF.
6. Connect a test lamp to ground and check for
voltage at the ignition voltage supply circuit at the
ECM (pin 36 of C-56 connector).
Does the test lamp illuminate?
Go to Step 6
Go to Step 14
6
1. Turn OFF the ignition.
2. Connect a DMM between the Keyword 2000
serial data circuit at the ECM (pin 32 of C-56
connector) and the EHCU (pin 11 of C-67
connector).
3. Test the circuits for an open circuit or high
resistance.
4. Repair the circuit(s) as necessary.
Did you find and correct the condition?
Go to Step 17
Go to Step 7
7
1. Turn OFF the ignition.
2. Connect a DMM between the Keyword 2000
serial data circuit at the EHCU (pin 11 of C-67
connector) and the DLC (pin 7 of B-58
connector).
3. Test the circuits for an open circuit or high
resistance.
4. Repair the circuit(s) as necessary.
Did you find and correct the condition?
Go to Step 17
Go to Step 8
Summary of Contents for 4ja1
Page 2: ......
Page 34: ...6A 12 ENGINE MECHANICAL Cooling and Lubricating System N m kg m lb ft RTW46AXF000701...
Page 35: ...ENGINE MECHANICAL 6A 13 Intake Manifold 4JA1TC 4JH1TC N m kg m lb ft RTW36AXF000201...
Page 36: ...6A 14 ENGINE MECHANICAL EGR Valve EGR Pipe EGR Cooler RTW46AXF000801...
Page 37: ...ENGINE MECHANICAL 6A 15 Exhaust Manifold and Turbocharger 4JA1L RTW46AXF000901...
Page 39: ...ENGINE MECHANICAL 6A 17 Engine Electricals N m kg m lb ft RTW36AXF000501...
Page 40: ...6A 18 ENGINE MECHANICAL Fuel Injection System 4JA1L N m kg m lb ft RTW86AXF000201...
Page 41: ...ENGINE MECHANICAL 6A 19 Fuel Injection System 4JA1TC N m kg m lb ft RTW46AXF001201...
Page 42: ...6A 20 ENGINE MECHANICAL Fuel Injection System 4JH1TC N m kg m lb ft RTW46AXF001301...
Page 43: ...ENGINE MECHANICAL 6A 21 Engine Mounting Bracket N m kg m lb ft 022R300001...
Page 162: ...MEMO...
Page 187: ...FUEL SYSTEM 6C 5 For EURO III model RTW46AMF000201...
Page 220: ...MEMO...
Page 225: ...ENGINE ELECTRICAL 6D 5 TORQUE SPECIFICATIONS GENERATOR N m kg m Ib ft RTW86DLF000101...
Page 226: ...6D 6 ENGINE ELECTRICAL STARTER MOTOR N m kg m Ib ft RTW86DLF000201...
Page 254: ...MEMO...
Page 261: ...Engine Control System 4JH1 6E 7 Engine Controls Schematics Power Distribution 1 RTW86EXF004801...
Page 262: ...6E 8 Engine Control System 4JH1 Power Distribution 2 RTW86EXF004901...
Page 263: ...Engine Control System 4JH1 6E 9 Starting System RTW86EXF005001...
Page 264: ...6E 10 Engine Control System 4JH1 Charging System RTW86EXF005101...
Page 265: ...Engine Control System 4JH1 6E 11 ECM Power and PCU RTW86EXF003001...
Page 266: ...6E 12 Engine Control System 4JH1 ECM Ground and DLC RTW86EXF005201...
Page 267: ...Engine Control System 4JH1 6E 13 Gauges and Warning Lamps RTW86EXF003201...
Page 269: ...Engine Control System 4JH1 6E 15 MAF IAT Vacuum Pressure and ECT Sensors RTW86EXF003401...
Page 275: ...Engine Control System 4JH1 6E 21 1 Legend 1 Vehicle Speed Sensor VSS...
Page 536: ...MEMO...
Page 558: ...6H 2 ACCELERATOR CONTROL REMOVAL AND INSTALLATION 4JA1T L RHD RTW46HLF000301...
Page 559: ...ACCELERATOR CONTROL 6H 3 4JA1T L LHD RTW46HLF000601...
Page 560: ...6H 4 ACCELERATOR CONTROL 4JA1TC 4JH1TC RHD RTW46HLF000201...
Page 561: ...ACCELERATOR CONTROL 6H 5 4JA1TC 4JH1TC LHD PTW46BMF000101...
Page 564: ...No TF4JE WE 1101...