Dodge Dakota (ND). Manual — part 1047

P0876-UD PRESSURE SWITCH RATIONALITY (CONTINUED)

6.

CHECK IF DTC EVENT DATA WAS SET IN PARK, NEUTRAL OR REVERSE

Refer to the DTC EVENT DATA recorded earlier.

Did the DTC P0876 set in Park, Neutral, or Reverse?

Yes

>> Go To 10

No

>> Go To 7

7.

CHECK FOR UD PRESSURE SWITCH STATUS

Refer to the DTC EVENT DATA recorded earlier.

Did the DTC P0876 set with the UD Pressure Switch closed?

Yes

>> Go To 10

No

>> Go To 8

8.

CHECK LINE PRESSURE

In the EATX DTC EVENT DATA recorded earlier, compare the Line Pressure and the Desired Line Pressure.

Is the Line Pressure less than 40 PSI, and significantly below the Desired Line Pressure?

Yes

>> Repair as necessary to correct low line pressure. Check fluid level and adjust as necessary. If fluid level

is OK, check the Primary Oil Filter seal for a split, crack, or improperly installed. If the filter and seal are
OK, check the Main Regulator Valve in the Oil Pump. Refer to the Service Information for the above
procedures.

Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST - VER 1.

No

>> Go To 9

9.

(T29) UD PRESSURE SWITCH SENSE CIRCUIT SHORT TO OTHER CIRCUITS

Turn the ignition off to the lock position.

Disconnect all PCM harness connectors.

Disconnect the Transmission Solenoid/TRS Assembly harness connec-
tor.

Measure the resistance between the (T29) UD Pressure Switch Sense
circuit and all other circuits in the Transmission Solenoid/TRS Assem-
bly harness connector.

Is the resistance below 5.0 ohms between the (T29) UD Pres-
sure Switch Sense circuit and any other circuit(s) in the Trans-
mission Solenoid/TRS Assembly harness connector?

Yes

>> Repair the (T29) UD Pressure Switch Sense circuit for a

short to other circuit(s).

Perform 45RFE/545RFE TRANSMISSION VERIFICATION
TEST - VER 1.

No

>> Replace the Transmission Solenoid/TRS Assembly per the

Service Information.

Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST - VER 1.

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P0876-UD PRESSURE SWITCH RATIONALITY (CONTINUED)

10.

PCM AND WIRING

Turn the ignition off to the lock position.

Remove the Starter Relay.

NOTE: Removal of the Starter Relay is to prevent a Transmission, NO RESPONSE, condition and disable the
starter.
Install the Transmission Simulator, Miller tool #8333.

NOTE: Check connectors - Clean/repair as necessary.
Ignition on, engine not running.

With the Transmission Simulator, turn the Pressure Switch selector switch to the UD position.

With the scan tool, monitor the UD Pressure Switch state while pressing the Pressure Switch Test button on the
Transmission Simulator.

Did the state of the UD Pressure Switch change while pressing the Pressure Switch Test button?

Yes

>> Go To 14

No

>> Go To 11

11.

(T29) UD PRESSURE SWITCH SENSE CIRCUIT OPEN

Turn the ignition off to the lock position.

Disconnect the Transmission Simulator, Miller tool #8333.

Disconnect the PCM C4 harness connector and connect Miller tool
#8815.

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 tool
#8815 to perform diagnosis.
Measure the resistance of the (T29) UD Pressure Switch Sense circuit
from the Transmission Solenoid/TRS Assembly harness connector and
the appropriate terminal of the special tool #8815.

Is the resistance above 5.0 ohms?

Yes

>> Repair the (T29) UD Pressure Switch Sense circuit for an

open.

Perform 45RFE/545RFE TRANSMISSION VERIFICATION
TEST - VER 1.

No

>> Go To 12

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P0876-UD PRESSURE SWITCH RATIONALITY (CONTINUED)

12.

(T29) UD PRESSURE SWITCH SENSE CIRCUIT SHORT TO GROUND

Measure the resistance between ground and the (T29) UD Pressure
Switch Sense circuit.

Is the resistance below 5.0 ohms?

Yes

>> Repair the (T29) UD Pressure Switch Sense circuit for a

short to ground.

Perform 45RFE/545RFE TRANSMISSION VERIFICATION
TEST - VER 1.

No

>> Go To 13

13.

(T29) UD PRESSURE SWITCH SENSE CIRCUIT SHORT TO ANOTHER CIRCUIT

Disconnect all PCM harness connectors.

NOTE: Make sure the Transmission Solenoid/TRS Assembly har-
ness connector is disconnected.
Measure the resistance between the (T29) UD Pressure Switch Sense
circuit and all other circuits in the Transmission Solenoid/TRS Assem-
bly harness connector.

Is the resistance below 5.0 ohms between the (T29) UD Pres-
sure Switch Sense circuit and any other circuit(s) in the Trans-
mission Solenoid/TRS Assembly harness connector?

Yes

>> Repair the (T29) UD Pressure Switch Sense circuit for a

short to another circuit(s).

Perform 45RFE/545RFE TRANSMISSION VERIFICATION
TEST - VER 1.

No

>> Using the schematics as a guide, check the Powertrain

Control Module (PCM) terminals for corrosion, damage, or
terminal push out. Pay particular attention to all power and ground circuits. If no problems are found,
replace the PCM per the Service Information. With the scan tool, perform QUICK LEARN.

Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST - VER 1.

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P0876-UD PRESSURE SWITCH RATIONALITY (CONTINUED)

14.

WIGGLE TEST WITH SIMULATOR

Perform the steps in the previous test while wiggling the wiring harness and connectors pertaining to the UD Pres-
sure Switch.

Did the state of the UD Pressure Switch change while pressing the Pressure Switch Test button?

Yes

>> Repair the wiring harness and/or connectors as necessary.

Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST - VER 1.

No

>> Go To 15

15.

CHECK FOR TRANSMISSION SOLENOID/TRS ASSEMBLY FOR A SHORT TO GROUND

Disconnect the Transmission Simulator and reconnect the Transmis-
sion Solenoid/TRS Assembly harness connector.

Disconnect the PCM C4 harness connector and connect Miller tool
#8815.

Measure the resistance between ground and the (T29) UD Pressure
Switch Sense circuit in the appropriate terminal of Miller tool #8815.

Is the resistance below 5.0 ohms?

Yes

>> Replace the Transmission Solenoid/TRS Assembly per the

Service Information.

Perform 45RFE/545RFE TRANSMISSION VERIFICATION
TEST - VER 1.

No

>> Go To 16

16.

CHECK IF DTC RESETS

Reconnect all previously disconnected connectors.

With the scan tool, erase all transmission DTCs.

Test drive the vehicle. Using the EATX DTC EVENT DATA recorded earlier, try to duplicate the conditions in which
the DTC originally set.

Does the DTC P0876 reset?

Yes

>> Go To 17

No

>> Go To 18

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