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Engine Controls - Tests W/codes - Body Control Computer: Overview Chrysler LHS I

Testing & Diagnostics 1 illustration ~2023 words

DESCRIPTION

The body control computer system consists of a combination of modules that communicate over the Chrysler Collision Detection (CCD) bus system. Through the CCD bus, information related to the operation of vehicle components and circuits is relayed to the appropriate system module(s). Each module receives the same information about a component. This reduces the complexity of vehicle wiring and size of wiring harness.

Body control computer systems covered in this article and BODY CONTROL COMPUTER TESTS are as follows: Automatic Door Locks (ADL), chime functions, compass/temperature module, courtesy lights, door ajar system, Electronic Instrument Cluster, Electronic Vehicle Information Center (ERIC), headlight time delay, illuminated entry system, Infinity radio, intermittent wipers, (ignition) key-in light system, Mechanical Instrument Cluster (MIC) warning lights, message center, Overhead Travel Information System (OTIS), Remote Keyless Entry (RKE) system, traveler module and Vehicle Theft Security System (VTSS).

Note. Self-diagnostic tests are written specifically for Chrysler's Diagnostic Readout Box (DRB) scan tool. A generic scan tool may not be capable of performing all necessary test functions.

Body Control Module Diagnostic Trouble Codes (DTCs) are accessed through CCD bus Data Link Connector (DLC) using Chrysler's Diagnostic Readout Box (DRB) scan tool or generic scan tool. DLC is a 6-pin connector located under instrument cluster, next to center console. (Scheme 17)

Scheme 17

Scheme 17: DESCRIPTION
Scheme 17: DESCRIPTION

The body control computer, also called Body Control Module (BCM), is located behind right side kick panel. BCM stores odometer information for electronic instrument cluster display and provides power and ground for a variety of systems.

BCM is the only module that has the capability of providing both "bias" and "termination" on the CCD bus system. See CCD BUS SYSTEM. Systems are monitored by BCM through voltage drops.

Vehicle may be equipped with either a premium or base model BCM. Base body control computer is used on vehicles with a mechanical instrument cluster and no EVIC.

Premium BCM can be identified by the presence of either the Automatic Temperature Control (ATC) system, Overhead Travel Information System (OTIS), or both.

TEST 67A - FUEL GAUGE/LAMP OPERATION FULL AT ALL TIMES

Note. For connector terminal identification, see CONNECTOR IDENTIFICATION . For wiring diagrams, see appropriate article in ENGINE PERFORMANCE

  1. «WIRING DIAGRAMS - 3.3L»(ref-11016)
  2. «WIRING DIAGRAMS - 3.5L»(/chrysler/lhs/i-1993-1997/remont/wiring-diagrams-engine-performance/#wiring-diagrams-35l)
  3. Perform TEST VER-1 after each repair. CAUTION: Always turn ignition off prior to disconnecting any module connector.
  1. Ensure fuel tank is not empty. Check if fuel gauge indicates full all the time. If fuel gauge does not indicate full all the time, go to TEST 68A. If fuel gauge indicates full all the time, go to next step.
  2. Start engine. Using scan tool, read body computer DTCs. If scan tool displays FUEL LEVEL SENDING UNIT, go to TEST 68A. If scan tool does not display FUEL LEVEL SENDING UNIT, go to next step.
  3. Turn ignition off. Access fuel pump connector. Connector is located on top of fuel tank and is accessible by removing access cover in floor of trunk. Disconnect fuel pump connector. Turn ignition on. Go to next step.
  4. Using scan tool, read fuel level sensor voltage. If voltage is more than 9 volts, replace fuel tank sending unit. If voltage is less than 9 volts, turn ignition off. Go to next step.
  5. Disconnect Body Control Module (BCM) Gray connector. BCM is located behind right kick panel. Using scan tool in ohmmeter mode, check resistance on BCM Gray connector terminal No. 23 (Dark Blue wire). If resistance is more than 5 ohms, replace BCM. If resistance is less than 5 ohms, go to next step.
  6. If vehicle is equipped with Flexible Fuel Module (FFM), go to next step. FFM is located in trunk behind trunk liner on rear passenger seat lower crossmember. If vehicle is not equipped with FFM, repair short to ground in Dark Blue wire.
  7. Disconnect FFM connector. Using scan tool in ohmmeter mode, check resistance of BCM connector terminal No. 23 (Dark Blue wire). If resistance is less than 5 ohms, repair short to ground in Dark Blue wire. If resistance is more than 5 ohms, go to next step.
  8. Check resistance of FFM connector terminal No. 3 (Light Blue/Black wire). If resistance is less than 5 ohms, repair short to ground in Light Blue/Black wire. If resistance is more than 5 ohms, replace FFM.

TEST 68C - FUEL GAUGE/LAMP OPERATION

Note. For connector terminal identification, see CONNECTOR IDENTIFICATION . For wiring diagrams, see appropriate article in ENGINE PERFORMANCE

  1. «WIRING DIAGRAMS - 3.3L»(ref-11016)
  2. «WIRING DIAGRAMS - 3.5L»(/chrysler/lhs/i-1993-1997/remont/wiring-diagrams-engine-performance/#wiring-diagrams-35l)
  3. Perform TEST VER-1 after each repair. CAUTION: Always turn ignition off prior to disconnecting any module connector.
  1. Gain access to Body Control Module (BCM). Turn ignition off. Disconnect BCM connectors. Turn ignition on. Go to next step.
  2. Using scan tool in voltmeter mode, check voltage on BCM Bone connector terminal No. 22 (Red/White wire). If voltage is less than 10 volts, repair open Red/White wire. If voltage is more than 10 volts, replace BCM.

TEST 105A - WIPER MOTOR HIGH SPEED OPERATION

Note. For connector terminal identification, see CONNECTOR IDENTIFICATION . For wiring diagrams, see appropriate article in ENGINE PERFORMANCE

  1. «WIRING DIAGRAMS - 3.3L»(ref-11016)
  2. «WIRING DIAGRAMS - 3.5L»(/chrysler/lhs/i-1993-1997/remont/wiring-diagrams-engine-performance/#wiring-diagrams-35l)
  3. Perform TEST VER-1 after each repair. CAUTION: Always turn ignition off prior to disconnecting any module connector.
  1. Gain access to Body Control Module (BCM). BCM is located behind right kick panel. Operate wipers in low speed mode. With BCM connectors connected, connect a jumper wire between BCM Bone connector terminal No. 18 (Violet wire) and chassis ground. If wiper speed changes to high mode, go to step 3). If wiper speed does not change, go to next step.
  2. Disconnect jumper wire. Move wiper switch to high speed mode. Using scan tool in voltmeter mode, backprobe BCM Bone connector terminal No. 16 (Dark Green/Red wire). If voltage is more than 8 volts, replace BCM. If voltage is less than 8 volts, replace multifunction switch.
  3. Disconnect jumper wire. Remove high/low wiper relay (relay No. 10) from Power Distribution Center (PDC). PDC is located on left front fender apron. see scheme 11 Go to next step.
  4. Using scan tool in voltmeter mode, check voltage on high/low wiper relay connector terminal "A" (Dark Blue wire). If voltage is less than 10 volts, repair open Dark Blue wire. If voltage is more than 10 volts, go to next step.
  5. Disconnect scan tool probe. Connect a jumper wire between high/low wiper relay connector terminals "B" (Light Green/Black wire) and "D" (Red/Yellow wire). If wipers operate in high speed mode, go to step 8). If wipers do not operate in high speed mode, go to next step.
  6. Leave jumper wire connected. Disconnect wiper motor connector. Connector is located on engine compartment firewall, just right of power brake booster. Go to next step.
  7. Using scan tool in voltmeter mode, check voltage on wiper motor connector terminal No. 2 (Red/Yellow wire). If voltage is less than 10 volts, repair open Red/Yellow wire. If voltage is more than 10 volts, replace wiper motor. 8) Turn ignition off. Disconnect jumper wire. With BCM connectors connected, connect jumper wire between BCM connector terminal No. 18 (Violet wire) and chassis ground. Using an external ohmmeter, check resistance between high/low wiper relay connector terminal "C" (Violet wire) and chassis ground. If resistance is less than 5 ohms, replace high/low wiper relay. If resistance is more than 5 ohms, repair open Violet wire.

TEST 106A - WIPER MOTOR LOW SPEED OPERATION

Note. For connector terminal identification, see CONNECTOR IDENTIFICATION . For wiring diagrams, see appropriate article in ENGINE PERFORMANCE

  1. «WIRING DIAGRAMS - 3.3L»(ref-11016)
  2. «WIRING DIAGRAMS - 3.5L»(/chrysler/lhs/i-1993-1997/remont/wiring-diagrams-engine-performance/#wiring-diagrams-35l)
  3. Perform TEST VER-1 after each repair. CAUTION: Always turn ignition off prior to disconnecting any module connector.
  1. Using scan tool, actuate wiper motor low speed. If wipers operate in low speed mode, go to step 6). If wipers do not operate in low speed, go to next step.
  2. Remove high/low wiper relay (relay No. 10) from Power Distribution Center (PDC). PDC is located on left front fender apron. see scheme 11 Go to next step.
  3. Connect a jumper wire between high low relay connector terminals "A" (Dark Blue wire) and "E" (Brown/White wire). If wiper motor operates in low speed mode, replace high/low wiper relay. If wiper motor does not operate in low speed mode, go to next step.
  4. Leave jumper wire connected. Disconnect wiper motor connector. Connector is located on engine compartment firewall, just right of power brake booster. Go to next step.
  5. Using scan tool in voltmeter mode, check voltage on wiper motor connector terminal No. 4 (Brown/White wire). If voltage is less than 10 volts, repair open Brown/White wire. If voltage is more than 10 volts, replace wiper motor.
  6. Stop wiper motor low speed actuation. Gain access to Body Control Module (BCM). BCM is located behind right kick panel. Leave BCM connectors connected. Move wiper switch to low. Go to next step.
  7. Using scan tool in voltmeter mode, backprobe BCM Bone connector terminal No. 16 (Dark Green/Red wire). If voltage is more than 6 volts, replace BCM. If voltage is less than 6 volts, replace multifunction switch.

TEST 107A - WIPER MOTOR INTERMITTENT SPEED OPERATION

Note. For connector terminal identification, see CONNECTOR IDENTIFICATION . For wiring diagrams, see appropriate article in ENGINE PERFORMANCE

  1. «WIRING DIAGRAMS - 3.3L»(ref-11016)
  2. «WIRING DIAGRAMS - 3.5L»(/chrysler/lhs/i-1993-1997/remont/wiring-diagrams-engine-performance/#wiring-diagrams-35l)
  3. Perform TEST VER-1 after each repair. CAUTION: Always turn ignition off prior to disconnecting any module connector.
  1. Turn ignition on. Move wiper switch through all 6 different delay (intermittent speed) levels. If all delay levels do not fail, go to step 3). If all delay levels fail, go to next step.
  2. Using scan tool, read wiper switch status. Move wiper switch from OFF position through all 6 different delay levels. If scan tool voltage does not increase proportionally between INTRMT WIPE 0V and 5V (volts), replace multifunction switch. If scan tool voltage does increase proportionally, replace BCM.
  3. Using scan tool, read wiper switch status at failed intermittent wiper switch position(s). If voltage is present at failed position, replace BCM. If voltage is not present at failed position, replace multifunction switch.

TEST 109A - WASHER PUMP OPERATION

Note. For connector terminal identification, see CONNECTOR IDENTIFICATION . For wiring diagrams, see appropriate article in ENGINE PERFORMANCE

  1. «WIRING DIAGRAMS - 3.3L»(ref-11016)
  2. «WIRING DIAGRAMS - 3.5L»(/chrysler/lhs/i-1993-1997/remont/wiring-diagrams-engine-performance/#wiring-diagrams-35l)
  3. Perform TEST VER-1 after each repair. CAUTION: Always turn ignition off prior to disconnecting any module connector.
  1. Ensure washer fluid reservoir is full. Check windshield washer pump operation. If washer pump does not operate, go to step 5). If washer pump operates and wipers operate, system is operating properly. If washer pump operates, but wipers do not operate, go to next step.
  2. Using scan tool, read washer switch status while pushing wash button. If scan tool displays WASHER SW CLOSED, replace Body Control Module (BCM). If scan tool does not display WASHER SW CLOSED, go to next step.
  3. Turn ignition off. Disconnect BCM Bone connector and multifunction switch connector. BCM is located behind right kick panel. Multifunction switch connector is located on upper part of steering column, behind trim cover. Go to next step.
  4. Using an external ohmmeter, check resistance of Brown wire between BCM Bone connector terminal No. 10 and multifunction switch connector terminal No. 2. If resistance is more than 5 ohms, repair open Brown wire. If resistance is less than 5 ohms, replace multifunction switch.
  5. Ensure washer fluid lines and nozzles are not damaged or restricted. Repair as necessary. If lines and nozzles are okay, go to next step.
  6. Disconnect windshield washer pump connector. Using scan tool in ohmmeter mode, check resistance of windshield washer pump connector terminal No. 2 (Black wire). If resistance is more than 5 ohms, repair open Black wire. If resistance is less than 5 ohms, go to next step.
  7. Push and hold windshield washer button on end of wiper/washer stalk. Using scan tool in voltmeter mode, check voltage on windshield washer pump connector terminal No. 1 (Brown wire). If voltage is less than 10 volts, repair open Brown wire between wiper/washer switch and windshield washer pump connector. If voltage is more than 10 volts, replace windshield washer pump.

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