Chrysler Town, Dodge Caravan. Manual — part 978

NOTES

10

7.0

DIAGNOSTIC INFORMATION AND

PROCEDURES

11

Symptom:

BUS SYSTEM COMMUNICATION FAILURE

When Monitored and Set Condition:

BUS SYSTEM COMMUNICATION FAILURE

When Monitored:

Ignition ON, continuously.

Set Condition:

When the CAB does not receive a message from the instrument cluster for

10 seconds.

POSSIBLE CAUSES

INTERMITTENT CONDITION

ELECTRO-MECHANICAL INSTRUMENT CLUSTER DTC PRESENT

BUS CIRCUIT OPEN

CAB - INTERNAL FAILURE

TEST

ACTION

APPLICABILITY

1

Turn the ignition on.
With the DRBIII

t, read DTCs.

With the DRBIII

t, read Freeze Frame information.

With the DRBIII

t, erase DTCs.

Turn the ignition off.
Turn the ignition on.
With the DRBIII

t, read DTCs.

Does the DRBIII

t display BUS SYSTEM COMMUNICATION FAILURE?

All

Yes

→ Go To 2

No

→ Go To 4

2

Turn the ignition on.
With the DRBIII

t, read EMIC DTCs.

Does the DRBIII

t display NO ABS MESSAGE RECEIVED?

All

Yes

→ Refer to symptom NO ABS MESSAGE RECEIVED in the BODY/

INSTRUMENT CLUSTER category.
Perform ABS VERIFICATION TEST - VER 1.

No

→ Go To 3

12

BRAKES (CAB)

TEST

ACTION

APPLICABILITY

3

Turn the ignition off.
Disconnect the negative (-) battery cable.
Disconnect the CAB harness connector.
NOTE: check connector - Clean/repair as necessary.
Measure the resistance of the Bus circuit between the CAB connector and the Data
Link Connector (DLC).
Is the resistance below 5.0 ohms?

All

Yes

→ Replace the Controller Antilock Brake in accordance with the

Service Information.
Perform ABS VERIFICATION TEST - VER 1.

No

→ Repair the Bus circuit for an open.

Perform ABS VERIFICATION TEST - VER 1.

4

Turn the ignition off.
Visually inspect the related wiring harness. Look for any chafed, pierced, pinched, or
partially broken wires.
Visually inspect the related wire harness connectors. Look for broken, bent, pushed
out, or corroded terminals.
Were any problems found?

All

Yes

→ Repair as necessary.

Perform ABS VERIFICATION TEST - VER 1.

No

→ Test Complete.

13

BRAKES (CAB)

BUS SYSTEM COMMUNICATION FAILURE —

Continued