Dodge Durango (HB). Manual — part 1175
P0846-2/4 PRESSURE SWITCH RATIONALITY (CONTINUED)
For the Transmission circuit diagram (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - 42RLE - SCHE-
MATICS AND DIAGRAMS)
For a complete wiring diagram Refer to Section 8W.
•
When Monitored:
Whenever the engine is running.
•
Set Condition:
The DTC is set if one of the pressure switches are open or closed at the wrong time in a given gear. If the
problem is identified for 3 successive key starts, the transmission will go into Limp-in mode and the MIL will
turn on after 10 seconds of vehicle operation.
Possible Causes
RELATED TRANSMISSION RELAY DTCS PRESENT
LOSS OF PRIME DTC PRESENT
(T47) 2/4 PRESSURE SWITCH SENSE CIRCUIT OPEN
(T47) 2/4 PRESSURE SWITCH SENSE CIRCUIT SHORT TO GROUND
(T47) 2/4 PRESSURE SWITCH SENSE CIRCUIT SHORT TO VOLTAGE
TRANSMISSION SOLENOID/PRESSURE SWITCH ASSEMBLY
POWERTRAIN CONTROL MODULE
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 21 - TRANSMIS-
SION/TRANSAXLE/AUTOMATIC - 42RLE - DIAGNOSIS AND TESTING).
Theory of Operation
The Transmission system uses three pressure switches to monitor the fluid pressure in the LR, 2/4, and OD ele-
ments. The pressure switches are continuously monitored for the correct states in each gear. The 2/4 pressure
switch monitors the fluid pressure to the 2/4 clutch to confirm proper operation of the 2/4 solenoid. If the 2/4 pres-
sure switch is identified as closed in P or N, the code will immediately be set and normal operation will be allowed
for that given key start. If the problem is identified for 3 successive ignition cycles, the transmission will go into
Limp-in mode.
PRESSURE SWITCH STATES
GEAR
L/R
2/4
OD
R
OP
OP
OP
P/N
CL
OP
OP
1st
CL
OP
OP
2nd
OP
CL
OP
D
OP
OP
CL
OD
OP
CL
CL
OP = OPEN
CL = CLOSED
HB
AUTOMATIC TRANSMISSION 42RLE - ELECTRICAL DIAGNOSTICS
21 - 105
P0846-2/4 PRESSURE SWITCH RATIONALITY (CONTINUED)
Diagnostic Test
1.
DETERMINING IF RELATED TRANSMISSION RELAY DTCS ARE PRESENT
With the scan tool, read Transmission DTCs
Are there any Transmission Control Relay DTCs present also?
Yes
>> Refer to the Transmission category and perform the appropriate symptom.
Perform 42RLE TRANSMISSION VERIFICATION TEST - VER 1.
No
>> Go To 2
2.
CHECK FOR LOSS OF PRIME DTC
With the scan tool, check for other Transmission DTCs.
Is the DTC P0944 present also?
Yes
>> Refer to the Transmission category and perform the appropriate diagnostic procedure.
Perform 42RLE TRANSMISSION VERIFICATION TEST - VER 1.
No
>> Go To 3
3.
CHECK TO SEE IF P0846 IS CURRENT
With the scan tool, view DTCs.
Is the status Active for this DTC or is the STARTS SINCE SET counter 2 or less?
Yes
>> Go To 4
No
>> Go To 10
4.
PCM AND WIRING
Turn the ignition off to the lock position.
Remove the Starter Relay.
CAUTION: Removal of the Starter Relay is to prevent a Transmission NO RESPONSE condition and to dis-
able the starter.
Install the Transmission Simulator, Miller tool #8333 and the Electronic Transmission Adapter kit 8333-1A.
NOTE: Check connectors - Clean/repair as necessary.
Ignition on, engine not running.
With the Transmission Simulator, turn the Pressure Switch selector to 2/4.
With the scan tool , monitor the 2/4 Pressure Switch state while pressing the Pressure Switch Test button on the
Transmission Simulator.
Did the 2/4 Pressure Switch state change?
Yes
>> Go To 8
No
>> Go To 5
21 - 106
AUTOMATIC TRANSMISSION 42RLE - ELECTRICAL DIAGNOSTICS
HB
P0846-2/4 PRESSURE SWITCH RATIONALITY (CONTINUED)
5.
(T47) 2/4 PRESSURE SWITCH SENSE CIRCUIT OPEN
Turn the ignition off to the lock position.
Disconnect the PCM C4 harness connector.
Disconnect the Transmission Solenoid/Pressure Switch Assembly har-
ness connector.
NOTE: Check connectors - Clean/repair as necessary.
CAUTION: Do not probe the PCM harness connectors. Probing
the PCM harness connectors will damage the PCM terminals
resulting in poor terminal to pin connection. Install Miller Special
Tool #8815 to perform diagnosis.
Measure the resistance of the (T47) 2/4 Pressure Switch Sense circuit
from the appropriate terminal of special tool #8815 to the Transmission
Solenoid/Pressure Switch Assembly harness connector.
Is the resistance above 5.0 ohms?
Yes
>> Repair the (T47) 2/4 Pressure Switch Sense circuit for an
open.
Perform 42RLE TRANSMISSION VERIFICATION TEST -
VER 1.
No
>> Go To 6
6.
(T47) 2/4 PRESSURE SWITCH SENSE CIRCUIT SHORT TO GROUND
Measure the resistance between ground and the (T47) 2/4 Pressure
Switch Sense circuit.
Is the resistance below 5.0 ohms?
Yes
>> Repair the (T47) 2/4 Pressure Switch Sense circuit for a
short to ground.
Perform 42RLE TRANSMISSION VERIFICATION TEST -
VER 1.
No
>> Go To 7
HB
AUTOMATIC TRANSMISSION 42RLE - ELECTRICAL DIAGNOSTICS
21 - 107
P0846-2/4 PRESSURE SWITCH RATIONALITY (CONTINUED)
7.
(T47) 2/4 PRESSURE SWITCH SENSE CIRCUIT SHORT TO VOLTAGE
Remove the Transmission Control Relay.
NOTE: Check connectors - Clean/repair as necessary.
Connect a jumper wire between the (A104) Fused B+ circuit and (T16)
Transmission Control Relay Output circuit.
Ignition on, engine not running.
Measure the voltage of the (T47) 2/4 Pressure Switch Sense circuit.
Is the voltage above 0.5 volts?
Yes
>> Repair the (T47) 2/4 Pressure Switch Sense circuit for a
short to voltage.
Perform 42RLE TRANSMISSION VERIFICATION TEST -
VER 1.
No
>> Go To 9
8.
2/4 PRESSURE SWITCH
If there are no possible causes remaining, view repair.
Repair
Replace the Transmission Solenoid/Pressure Switch Assembly per the Service Information.
Perform 42RLE TRANSMISSION VERIFICATION TEST - VER 1.
9.
POWERTRAIN CONTROL MODULE
Using the schematics as a guide, inspect the wiring and connectors. Repair as necessary. Pay particular attention
to all power and ground circuits.
If there are no possible causes remaining, view repair.
Repair
Replace the Powertrain Control Module per the Service Information. With the scan tool perform QUICK
LEARN.
Perform 42RLE TRANSMISSION VERIFICATION TEST - VER 1.
21 - 108
AUTOMATIC TRANSMISSION 42RLE - ELECTRICAL DIAGNOSTICS
HB
Нет комментариевНе стесняйтесь поделиться с нами вашим ценным мнением.
Текст