Dodge Nitro. Manual — part 348

No

Testing is complete.

NAG1 PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE

For complete wiring diagrams refer to SYSTEM WIRING DIAGRAMS article.

Perform the following pre-diagnostic troubleshooting procedures prior to performing any diagnostic test.

Always perform diagnostics with a fully charged battery to avoid false symptoms.

1. With the scan tool, read the engine DTCs. Check and repair all engine DTCs prior to performing

transmission symptom diagnostic procedures.

2. With the scan tool, read and record all Transmission DTCs. Record the controller software version and

variant ID (configuration or level).

3. Verify the current software level of transmission controller. Various problems are corrected by software

upgrades (flash) to the transmission controller.

4. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors to all components

related to the transmission and shift lever assembly. Clean and repair as necessary.

5. Most DTCs set on start up but some may only set by driving the vehicle. Note the when monitored and

set conditions of the reported DTC. If variant DTCs are present, perform their respective test first.

NOTE:

Due to different power control configurations, the Transmission Control Relay
(if equipped) may be referred to as a PCM relay.

NOTE:

Incorrect fluid level, and/or poor fluid condition can be the cause of many
transmission problems. Visually inspect the transmission and cooler lines for
leakage and repair as necessary and adjust the fluid level per the Service
Information.

NOTE:

Check for any Service Information Tune-ups or Technical Service Bulletins
(TSB) that may apply.

NOTE:

If the TCM detects and stores a DTC, the TCM also stores the vehicles
operating conditions under which the DTC originally set. This information
is located using a scan tool under Environmental Data. Before erasing any
stored DTCs, it is recommended to record all available data to assist in
troubleshooting and duplicating the conditions and in which the DTC
originally set.

NOTE:

If a TCM software update is performed, all DTC information (Environmental
Data) will be lost.

2007 Dodge Nitro R/T

2007 AUTOMATIC TRANSMISSION NAG1 - Shifter Diagnostics - Nitro

6. Verify the axle ratio and transfer case ratio.

Did any of the above procedures repair the vehicle?

Yes

Testing is complete.

Perform NAG1 TRANSMISSION VERIFICATION TEST.

No

Refer to the identified category and perform the appropriate symptom(s).

NOTE:

The Transfer case ratio must be programmed using the scan tool under
the appropriate gateway module (FCM, FDCM, and/or TIPM) even if
equipped with AWD or NO transfer case. Validate that the left to right tire
sizes on each axle are the same. Do not perform diagnostics using a
space-saver spare tire. Invalid tire sizes (right to left) may cause erroneous
DTCs to set.

2007 Dodge Nitro R/T

2007 AUTOMATIC TRANSMISSION NAG1 - Shifter Diagnostics - Nitro

CONVERTER-TORQUE

DESCRIPTION

TORQUE CONVERTER

Fig. 267: Cutaway View Of Torque Converter
Courtesy of CHRYSLER LLC

1 - TURBINE
2 - IMPELLER

2007 Dodge Nitro R/T

2007 AUTOMATIC TRANSMISSION NAG1 - Service Information - Nitro

2007 Dodge Nitro R/T

2007 AUTOMATIC TRANSMISSION NAG1 - Service Information - Nitro

The torque converter is a hydraulic device that couples the engine crankshaft to the transmission. The torque
converter consists of an outer shell with an internal turbine (1), a stator (3), an overrunning clutch, an impeller
(2), and an electronically applied converter clutch. The converter clutch provides reduced engine speed and
greater fuel economy when engaged. Clutch engagement also provides reduced transmission fluid temperatures.
The converter clutch engages in third through fifth gears. The torque converter hub drives the transmission oil
(fluid) pump. See Fig. 267.

A turbine damper (6) has been added for some applications to help improve vehicle noise, vibration, and
harshness (NVH) characteristics.

The torque converter is a sealed, welded unit that is not repairable and is serviced as an assembly.

IMPELLER

Fig. 268: Impeller

3 - STATOR
4 - INPUT SHAFT
5 - STATOR SHAFT
6 - TURBINE DAMPER

CAUTION: The torque converter must be replaced if a transmission failure resulted in

large amounts of metal or fiber contamination in the fluid.

2007 Dodge Nitro R/T

2007 AUTOMATIC TRANSMISSION NAG1 - Service Information - Nitro