Module Communications Network Ford Cutaway E350

The module communications network consists of the following

1. anti-lock brake system (ABS) module
2. instrument cluster
3. powertrain control module (PCM)
4. restraint control module (RCM)
5. vehicle security module

Refer to SYSTEM WIRING DIAGRAMS for schematic and connector information.

SPECIAL TOOLS 73III Automotive Meter 105-R0057 or equivalent Worldwide Diagnostic System (WDS) Vehicle Communication Module (VCM) with appropriate adapters, or equivalent diagnostic tool

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Principles of Operation

The vehicle has 2 module communications network protocols

1. International Standards Organization (ISO) 9141 communications network
2. controller area network (CAN)

The ISO 9141 communications network is a single wire communications network circuit 70 (LB/WH). The CAN is an unshielded, twisted pair cable communications network, circuit 1827 (WH/LG) and circuit 1828 (PK/LG). Both communications networks are connected to the data link connector (DLC). This makes diagnosis and testing of these systems easier by allowing one diagnostic tool to be able to diagnose and control any module on the communications networks from one connector. The DLC can be found under the instrument panel and the steering column.

The ISO 9141 communications network does not permit intermodule communication. When the diagnostic tool communicates to modules on the ISO 9141 communications network, the diagnostic tool must ask for all information; the modules cannot initiate communications. The ISO 9141 communications network does not function if the circuit is shorted to ground or battery voltage. Also, if one of the modules on the ISO 9141 communications network loses power or shorts internally, communications to that module fail.

Anti-Lock Brake System (ABS)

Module The ABS module is on the ISO 9141 communications network. The ABS module controls the brake pressure to the 4 wheels to keep the vehicle under control while braking. The ISO 9141 communications network does not function if the circuit is shorted to ground or battery voltage. Check the communications network circuit 70 (LB/WH) between the ABS module C135 and the DLC C251. The total resistance value must not be more than 5 ohms. If the resistance is more than 5 ohms, there is an open circuit in the ISO 9141 communications network, damage to the DLC C251, damage to the ABS module C135, or a problem in the in-line connector. For additional information, refer to ANTI-LOCK CONTROL .

Instrument Cluster

The instrument cluster is on the CAN. It is an analog face cluster with a digital odometer. The instrument cluster displays a variety of information. Check the communications network circuits 1827 (WH/LG) and 1828 (PK/LG) between the instrument cluster C220a and the DLC C251. The total resistance values must not be more than 5 ohms. If the resistance is more than 5 ohms there is an open circuit in the CAN, damage to the DLC C251, damage to the instrument cluster C220a, or a problem in the in-line connector. For additional information, refer to INSTRUMENT CLUSTER .

Powertrain Control Module (PCM)

The PCM is on the CAN. The PCM controls the engine for better fuel economy, emissions control, failure mode detection and storage. If one of the communications network circuits become shorted to ground or voltage, or if some but not all termination resistors are lost, communications can continue. Check the communications network circuits 1827 (WH/LG) and 1828 (PK/LG) between the PCM C175 (gasoline) or PCM C176a (diesel) and the DLC C251. The total resistance values must not be more than 5 ohms. If the resistance is more than 5 ohms there is an open circuit in the CAN, damage to the DLC C251, damage to the PCM C175 (gasoline), damage to the PCM C176a (diesel) or a problem in the in-line connector. For additional information, See INTRODUCTION - GASOLINE and/or INTRODUCTION -- 6.0L DIESEL articles.

Restraint Control Module (RCM)

The RCM is on the ISO 9141 communications network. The RCM controls the deployment of the air bags based on sensor input. The ISO 9141 communications network does not function if the circuit is shorted to ground or battery voltage. Check the communications network circuit 70 (LB/WH) between the RCM C310a and the DLC C251. The total resistance value must not be more than 5 ohms. If the resistance is more than 5 ohms, there is an open circuit in the ISO 9141 communications network, damage to the DLC C251, damage to the RCM C310a, or a problem in the in-line connector. For additional information, refer to SUPPLEMENTAL RESTRAINT SYSTEM .

Vehicle Security Module

The vehicle security module is on the ISO 9141 communications network. The vehicle security module controls the remote keyless entry (RKE) function as well as the power door locks. The ISO 9141 communications network does not function if the circuit is shorted to ground or battery voltage. Check the communications network circuit 70 (LB/WH) between the vehicle security module C203b and the DLC C251. The total resistance value must not be more than 5 ohms. If the resistance is more than 5 ohms, there is an open circuit in the ISO 9141 communications network, damage to the DLC C251, damage to the vehicle security module C203b, or a problem in the in-line connector. For additional information, refer to MULTIFUNCTION ELECTRONIC MODULES .

Inspection and Verification

1. Verify the customer concern.
2. Visually inspect for obvious signs of electrical damage. VISUAL INSPECTION CHART Electrical Battery junction box (BJB) fuse 18 (60A) Central junction box (CJB) fuse 26 (20A) Wiring harness Connections
3. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.
4. If the cause is not visually evident, connect the diagnostic tool to the DLC and select the vehicle to be tested from the diagnostic tool menu. If the diagnostic tool does not communicate with the vehicle: check that the program card is correctly installed. check the connections to the vehicle. check the ignition switch position.
5. If the diagnostic tool still does not communicate with the vehicle, refer to the diagnostic tool operating manual.
6. GO to «PINPOINT TEST PC»(/ford/cutaway-e350/2004-2007/remont/communication-devices/#module-communications-network__pinpoint-test-pc-data-link-diagnostics) .

DIAGNOSTIC TROUBLE CODE (DTC) CHART

PINPOINT TEST PC: DATA LINK DIAGNOSTICS TEST

1. PC1 RUN THE DIAGNOSTIC TOOL DATA LINK TEST Key in ON position. Enter the following diagnostic mode on the diagnostic tool: Diagnostic Tool Data Link Test. Does the diagnostic tool indicate system passed? Yes : Test passed. RETURN to the «Symptom Chart»(/ford/cutaway-e350/2004-2007/remont/communication-devices/#module-communications-network__symptom-chart) for the module in question. No : If ISO 9141 communications network circuit faults; all electronic control units no response/not equipped, GO to «PINPOINT TEST G»(/ford/cutaway-e350/2004-2007/remont/communication-devices/#module-communications-network) . If controller area network (CAN) circuit faults; all electronic control units no response/not equipped, GO to «PINPOINT TEST F»(/ford/cutaway-e350/2004-2007/remont/communication-devices/#module-communications-network) . If no response from the diagnostic tool, GO to «PINPOINT TEST H»(/ford/cutaway-e350/2004-2007/remont/communication-devices/#module-communications-network) . If only one module does not communicate with the diagnostic tool, GO to «SYMPTOM CHART»(/ford/cutaway-e350/2004-2007/remont/communication-devices/#module-communications-network__symptom-chart) .

Symptom Chart

MODULE COMMUNICATIONS NETWORK SYMPTOM CHART

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1. A1 CHECK FOR AN OPEN BETWEEN THE PCM AND THE DATA LINK CONNECTOR (DLC) C251 Key in OFF position. Disconnect: PCM C175 (Gasoline). Disconnect: PCM C176a (Diesel). On gasoline engines, measure the resistance between the PCM C175-11, circuit 1827 (WH/LG), harness side and DLC C251-6, circuit 1827 (WH/LG), harness side. On gasoline engines, measure the resistance between the PCM C175-23, circuit 1828 (PK/LG), harness side and DLC C251-14, circuit 1828 (PK/LG), harness side. On diesel engines, measure the resistance between the PCM C176a-13, circuit 1827 (WH/LG), harness side and DLC C251-6, circuit 1827 (WH/LG), harness side. On diesel engines, measure the resistance between the PCM C176a-14, circuit 1828 (PK/LG), harness side and DLC C251-14, circuit 1828 (PK/LG), harness side. Are the resistances less than 5 ohms? Yes : GO to A2. No : REPAIR the circuit in question. CLEAR the diagnostic trouble codes (DTCs). REPEAT the self-test. CARRY OUT the diagnostic tool data link test.
2. A2 CHECK FOR CORRECT PCM OPERATION Disconnect all the PCM connectors. Check for: corrosion push-out pins Connect all the PCM connectors and make sure they seat correctly. Operate the system and verify the concern is still present. Is the concern still present? Yes : INSTALL a new PCM. REFER to «ELECTRONIC ENGINE CONTROLS - GASOLINE ENGINES»(/ford/cutaway-e350/2004-2007/remont/removal-installation/#electronic-engine-controls-gasoline-engines) or «ELECTRONIC ENGINE CONTROLS - GASOLINE ENGINES»(/ford/cutaway-e350/2004-2007/remont/removal-installation/#electronic-engine-controls-diesel-engine-e350-e450) . CLEAR the DTCs. REPEAT the self-test. CARRY OUT the diagnostic tool data link test. No : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test. CARRY OUT the diagnostic tool data link test.

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1. B1 CHECK FOR AN OPEN BETWEEN THE INSTRUMENT CLUSTER C220A AND THE DATA LINK CONNECTOR (DLC) C251 Key in OFF position. Disconnect: Instrument Cluster C220a. Measure the resistance between the instrument cluster C220a-9, circuit 1827 (WH/LG), harness side and DLC C251-6, circuit 1827 (WH/LG), harness side. Measure the resistance between the instrument cluster C220a-i circuit 1828 (PK/LG), harness side and DLC C251-14, circuit 1828 (PK/LG), harness side. Are the resistances less than 5 ohms? Yes : GO to B2. No : REPAIR the circuit in question. CLEAR the diagnostic trouble codes (DTCs). REPEAT the self-test. CARRY OUT the diagnostic tool data link test.
2. B2 CHECK FOR CORRECT INSTRUMENT CLUSTER OPERATION Disconnect all the instrument cluster connectors. Check for: corrosion push-out pins Connect all the instrument cluster connectors and make sure they seat correctly. Operate the system and verify the concern is still present. Is the concern still present? Yes : INSTALL a new instrument cluster. REFER to «INSTRUMENT CLUSTER»(ref-231355) . CLEAR the DTCs. REPEAT the self-test. CARRY OUT the diagnostic tool data link test. No : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test. CARRY OUT the diagnostic tool data link test.

Scheme 9

1. C1 CHECK FOR AN OPEN BETWEEN THE RCM C310A AND THE DATA LINK CONNECTOR (DLC) C251 Key in OFF position. Depower the supplemental restraint system (SRS). Refer to «SUPPLEMENTAL RESTRAINT SYSTEM»(/ford/cutaway-e350/2004-2007/remont/airbag/#supplemental-restraint-system) . Disconnect: RCM C310a. Measure the resistance between the RCM C310a-11, circuit 70 (LB/WH), harness side and the DLC C251-7, circuit 70 (LB/WH), harness side. Are the resistances less than 5 ohms? Yes : GO to C2. No : REPAIR the circuit. CLEAR the diagnostic trouble codes (DTCs). REPEAT the self-test. CARRY OUT the diagnostic tool data link test.
2. C2 CHECK FOR CORRECT RCM OPERATION Disconnect all the RCM connectors. Check for: corrosion push-out pins Connect all the RCM connectors and make sure they seat correctly. Operate the system and verify the concern is still present. Is the concern still present? Yes : INSTALL a new RCM. REFER to «SUPPLEMENTAL RESTRAINT SYSTEM»(/ford/cutaway-e350/2004-2007/remont/airbag/#supplemental-restraint-system) . CLEAR the DTCs. REPEAT the self-test. CARRY OUT the diagnostic tool data link test. No : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test. CARRY OUT the diagnostic tool data link test.

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1. D1 CHECK FOR AN OPEN BETWEEN THE ABS MODULE C135 AND THE DATA LINK CONNECTOR (DLC) C251 Key in OFF position. Disconnect: ABS Module C135. Measure the resistance between the ABS module C135-1, circuit 70 (LB/WH), harness side and the DLC C251-7, circuit 70 (LB/WH), harness side. Is the resistance less than 5 ohms? Yes : GO to D2. No : REPAIR the circuit. CLEAR the diagnostic trouble codes (DTCs). REPEAT the self-test. CARRY OUT the diagnostic tool data link test.
2. D2 CHECK FOR CORRECT ABS MODULE OPERATION Disconnect all the ABS module connectors. Check for: corrosion push-out pins Connect all the ABS module connectors and make sure they seat correctly. Operate the system and verify the concern is still present. Is the concern still present? Yes : INSTALL a new ABS module. REFER to «ANTI-LOCK CONTROL»(/ford/cutaway-e350/2004-2007/remont/anti-locktraction-control/#anti-lock-brake-system-anti-lock-control) . CLEAR the DTCs. REPEAT the self-test. CARRY OUT the diagnostic tool data link test. No : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test. CARRY OUT the diagnostic tool data link test.

Scheme 11

1. E1 CHECK FOR AN OPEN BETWEEN THE VEHICLE SECURITY MODULE C203B AND THE DATA LINK CONNECTOR (DLC) C251 Key in OFF position. Disconnect: Vehicle Security Module C203b. Measure the resistance between the vehicle security module C203b-3, circuit 70 (LB/WH), harness side and the DLC C251-7, circuit 70 (LB/WH), harness side. Is the resistance less than 5 ohms? Yes : GO to E2. No : REPAIR the circuit. CLEAR the diagnostic trouble codes (DTCs). REPEAT the self-test. CARRY OUT the diagnostic tool data link test.
2. E2 CHECK FOR CORRECT VEHICLE SECURITY MODULE OPERATION Disconnect all the vehicle security module connectors. Check for: corrosion push-out pins Connect all the vehicle security module connectors and make sure they seat correctly. Operate the system and verify the concern is still present. Is the concern still present? Yes : INSTALL a new vehicle security module. REFER to «MULTIFUNCTION ELECTRONIC MODULES»(/ford/cutaway-e350/2004-2007/remont/communication-devices/#multifunction-electronic-modules) . CLEAR the DTCs. REPEAT the self-test. CARRY OUT the diagnostic tool data link test. No : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test. CARRY OUT the diagnostic tool data link test.

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1. F1 CHECK FOR AN OPEN BETWEEN THE INSTRUMENT CLUSTER C220A AND THE DATA LINK CONNECTOR (DLC) C251 Key in OFF position. Disconnect: Instrument Cluster C220a. Measure the resistance between the instrument cluster C220a-9, circuit 1827 (WH/LG), harness side and DLC C251-6, circuit 1827 (WH/LG), harness side. Measure the resistance between the instrument cluster C220a-8, circuit 1828 (PK/LG), harness side and DLC C251-14, circuit 1828 (PK/LG), harness side. Are the resistances less than 5 ohms? Yes : GO to F2. No : REPAIR the circuit in question. CLEAR the diagnostic trouble codes (DTCs). REPEAT the self-test. CARRY OUT the diagnostic tool data link test.
2. F2 CHECK THE CAN WITH THE INSTRUMENT CLUSTER C220A DISCONNECTED Key in ON position. Enter the following diagnostic mode on the diagnostic tool: Data Link Diagnostics Test. Does the diagnostic tool indicate system passed? Yes : GO to F6 . No : GO to F3.
3. F3 CHECK THE CAN CIRCUITS FOR A SHORT TO GROUND Key in OFF position. Disconnect: PCM C175 (gasoline) or PCM C176a (diesel). Disconnect: Instrument Cluster C220a. Measure the resistance between the DLC C251-6, circuit 1827 (WH/LG), harness side and ground; and between the DLC C251-14, circuit 1828 (PK/LG), harness side and ground Are the resistances greater than 10,000 ohms? Yes : GO to F4. No : REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test. CARRY OUT the diagnostic tool data link test.
4. F4 CHECK THE CAN CIRCUITS FOR A SHORT TO VOLTAGE Key in ON position. Measure the voltage between the DLC C251-6, circuit 1827 (WH/LG), harness side and ground; and between the DLC C251-14, circuit 1828 (PK/LG), harness side and ground. Is any voltage indicated? Yes : REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test. CARRY OUT the diagnostic tool data link test. No : GO to F5.
5. F5 CHECK FOR CORRECT PCM OPERATION Disconnect all the PCM connectors. Check for: corrosion pushed-out pins Connect all the PCM connectors and make sure they seat correctly. Operate the system and verify the concern is still present. Is the concern still present? Yes : INSTALL a new PCM. REFER to «ELECTRONIC ENGINE CONTROLS - GASOLINE ENGINES»(/ford/cutaway-e350/2004-2007/remont/removal-installation/#electronic-engine-controls-gasoline-engines) or «ELECTRONIC ENGINE CONTROLS - GASOLINE ENGINES»(/ford/cutaway-e350/2004-2007/remont/removal-installation/#electronic-engine-controls-diesel-engine-e350-e450) . CARRY OUT the diagnostic tool data link test. No : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test. CARRY OUT the diagnostic tool data link test.
6. F6 CHECK FOR CORRECT INSTRUMENT CLUSTER OPERATION Disconnect all the instrument cluster connectors. Check for: corrosion push-out pins Connect all the instrument cluster connectors and make sure they seat correctly. Operate the system and verify the concern is still present. Is the concern still present? Yes : INSTALL a new instrument cluster. REFER to «INSTRUMENT CLUSTER»(ref-231355) . CLEAR the DTCs. REPEAT the self-test. CARRY OUT the diagnostic tool data link test. No : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test. CARRY OUT the diagnostic tool data link test.

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1. G1 CHECK ISO 9141 COMMUNICATIONS NETWORK CIRCUIT 70 (LB/WH) BETWEEN THE DATA LINK CONNECTOR (DLC) C251 AND THE RESTRAINTS CONTROL MODULE (RCM) C310A FOR AN OPEN Key in OFF position. Depower the supplemental restraint system (SRS). Refer to «SUPPLEMENTAL RESTRAINT SYSTEM»(/ford/cutaway-e350/2004-2007/remont/airbag/#supplemental-restraint-system) . Disconnect: RCM C310a. Measure the resistance between the RCM C310a-11, circuit 70 (LB/WH), harness side and the DLC C251-7, circuit 70 (LB/WH), harness side. Is the resistance less than 5 ohms? Yes : GO to G2. No : REPAIR the circuit. CLEAR the diagnostic trouble codes (DTCs). REPEAT the self-test. CARRY OUT the diagnostic tool data link test.
2. G2 CHECK THE ISO 9141 COMMUNICATIONS NETWORK WITH THE RCM C310A DISCONNECTED Key in ON position. Enter the following diagnostic mode on the diagnostic tool: Data Link Diagnostics Test. Does the diagnostic tool indicate system passed? Yes : GO to G7 . No : If equipped with anti-lock brake system (ABS), GO to G3. If not equipped with ABS, GO to G5 .
3. G3 CHECK ISO 9141 COMMUNICATIONS NETWORK CIRCUIT 70 (LB/WH) BETWEEN THE DLC C251 AND THE ABS MODULE C135 FOR AN OPEN Key in OFF position. Connect: RCM C310a. Disconnect: ABS Module C135. Measure the resistance between the ABS module C135-1, circuit 70 (LB/WH), harness side and the DLC C251-7, circuit 70 (LB/WH), harness side. Is the resistance less than 5 ohms? Yes : GO to G4. No : REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test. CARRY OUT the diagnostic tool data link test.
4. G4 CHECK THE ISO 9141 COMMUNICATIONS NETWORK WITH THE ABS MODULE C135 DISCONNECTED Key in ON position. Enter the following diagnostic mode on the diagnostic tool: Data Link Diagnostics Test. Does the diagnostic tool indicate system passed? Yes : GO to G8 . No : GO to G5.
5. G5 CHECK THE ISO 9141 COMMUNICATIONS NETWORK CIRCUIT FOR A SHORT TO GROUND Key in OFF position. Disconnect: RCM C310a. Disconnect: ABS Module C135 (if equipped). Disconnect: Vehicle Security Module C203b (if equipped). Measure the resistance between the DLC C251-7, circuit 70 (LB/WH), harness side and ground. Is the resistance greater than 10,000 ohms? Yes : GO to G6. No : REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test. CARRY OUT the diagnostic tool data link test.
6. G6 CHECK THE ISO 9141 COMMUNICATIONS NETWORK CIRCUIT FOR A SHORT TO VOLTAGE Key in ON position. Measure the voltage between the DLC C251-7, circuit 70 (LB/WH), harness side and ground. Is any voltage indicated? Yes : REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test. CARRY OUT the diagnostic tool data link test. No : If equipped with a vehicle security module GO to G9 . If not equipped with a vehicle security module, GO to G7.
7. G7 CHECK FOR CORRECT RCM OPERATION Disconnect all the RCM connectors. Check for: corrosion push-out pins Connect all the RCM connectors and make sure they seat correctly. Operate the system and verify the concern is still present. Is the concern still present? Yes : INSTALL a new RCM. REFER to «SUPPLEMENTAL RESTRAINT SYSTEM»(/ford/cutaway-e350/2004-2007/remont/airbag/#supplemental-restraint-system) . CLEAR the DTCs. REPEAT the self-test. CARRY OUT the diagnostic tool data link test. No : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test. CARRY OUT the diagnostic tool data link test.
8. G8 CHECK FOR CORRECT ABS MODULE OPERATION Disconnect all the ABS module connectors. Check for: corrosion pushed-out pins Connect all the ABS module connectors and make sure they seat correctly. Operate the system and verify the concern is still present. Is the concern still present? Yes : INSTALL a new ABS module. Refer to «ANTI-LOCK CONTROL»(/ford/cutaway-e350/2004-2007/remont/anti-locktraction-control/#anti-lock-brake-system-anti-lock-control) . CLEAR the DTCs. REPEAT the self-test. CARRY OUT the diagnostic tool data link test. No : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test. CARRY OUT the diagnostic tool data link test.
9. G9 CHECK FOR CORRECT VEHICLE SECURITY MODULE OPERATION Disconnect all the vehicle security module connectors. Check for: corrosion push-out pins Connect all the vehicle security module connectors and make sure they seat correctly. Operate the system and verify the concern is still present. Is the concern still present? Yes : INSTALL a new vehicle security module. REFER to «MULTIFUNCTION ELECTRONIC MODULES»(/ford/cutaway-e350/2004-2007/remont/communication-devices/#multifunction-electronic-modules) . CLEAR the DTCs. REPEAT the self-test. CARRY OUT the diagnostic tool data link test. No : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test. CARRY OUT the diagnostic tool data link test.

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1. H1 CHECK THE DIAGNOSTIC TOOL CONNECTOR Inspect the diagnostic tool pins for damage. Are the pins OK? Yes : GO to H2. No : REPAIR the diagnostic tool connector. CARRY OUT the diagnostic tool data link test.
2. H2 CHECK THE DATA LINK CONNECTOR (DLC) C251 FOR DAMAGE Key in OFF position. Inspect the DLC C251 pins for damage. Are the pins OK? Yes : GO to H3. No : REPAIR the DLC C251. CARRY OUT the diagnostic tool data link test.
3. H3 CHECK THE VOLTAGE TO THE DLC C251 CIRCUIT 40 (LB/WH) Measure the voltage between the DLC C251-16, circuit 40 (LB/WH), harness side and ground. Is the voltage greater than 10 volts? Yes : GO to H4. No : REPAIR the circuit. CARRY OUT the diagnostic tool data link test.
4. H4 CHECK THE DLC GROUND CIRCUIT 875 (BK/LB) AND CIRCUIT 570 (BK) Measure the resistance between the DLC C251-4, circuit 875 (BK/LB), harness side and ground; and between the DLC C251-5, circuit 570 (BK), harness side and ground. Are the resistances less than 5 ohms? Yes : REPAIR the diagnostic tool. CARRY OUT the diagnostic tool data link test. No : REPAIR the circuit in question. CARRY OUT the diagnostic tool data link test.

See also:
• ANTI-LOCK CONTROL
• INTRODUCTION - GASOLINE
• INTRODUCTION -- 6.0L DIESEL
• SUPPLEMENTAL RESTRAINT SYSTEM
• MULTIFUNCTION ELECTRONIC MODULES
• ELECTRONIC ENGINE CONTROLS - GASOLINE ENGINES
• ELECTRONIC ENGINE CONTROLS - GASOLINE ENGINES
• PINPOINT TEST PC
• PINPOINT TEST B
• Symptom Chart