rusefi_documentation/NAG1---722.6.md

# NAG1 722.6

## CANBUS Inputs

The TCM CAN bus inputs used by the NAG 1 electronic control system are:

* ABS Wheel Speed Sensors (two-wheel drive uses rear sensors, four-wheel drive
uses front and rear sensors)
* Engine Coolant Temperature
* Engine Static Torque
* Driver Input Requested Torque
* Pedal Position
* Demanded Engine Torque (Electronic Stability Program [ESP])
* Engine RPM
* Brake Light Switch
* Cruise Control Off Signal
* Limp-In Mode Message (from PCM on Grand Cherokee and Sprinter)
* Acknowledge Transmission Torque Request
* Cluster Ambient Air Temperature
* Shift Lever Position (from SLA)
* Winter/Standard Switch (Crossfire)
* FCM Inputs to TCM
* — Axle Ratio
* — Transfer Case
* — Dynamic Tire Circumference
* — Model Year
* — Country Code
* — Body Style
* — Odometer
* — Brake Light Switch
* — Kickdown Signal
* — Ignition Switch Status (Key In, Ignition Off Active, Ignition Run, Ignition
* Start Active)

The SLA (Shift Lever Assembly) processes the following information:

* Stop lamp speed control signal (service brake)
* Shift lever position (internal to module)
* Request ID
* Brake pedal depressed
* Vehicle speed signal from ABS/ESP controller
* Ignition switch status
* Odometer
* VIN message information
* Network configuration
* Vehicle information
The SLA outputs the following signals:
* SLA Status
* Response ID

The following are the output signals the TCM transmits over the CAN bus.

* Current/Actual/Target Gear (TCM to CAB/PCM)
* Maximum Engine Torque
* Minimum/Maximum Transmission Torque
* Requested Engine Torque
* Calculated Output Shaft Speed
* Allow Transmission Torque Request
* Torque Converter Status (Open, Closed, Slipping, Open Slipping [5%], Closed
Slipping [95%])
* Kickdown
* Transmission Overtemp (to PCM)
* Transmission in Limp-In Mode (to PCM)
* OK to Crank (to PCM)
* Garage Shift Torque Demand
* Output Shaft Torque (CAB/EPS Option Only)
* PRNDL Display Request (to FCM and FCM to Cluster, Sprinter is Shifter to
* Cluster)
* Transmission Fluid Temperature
* PRNDL Status (Signal Not Available)
* Freeze Frame DTC
* Number of DTCs Stored (Set)
* MIL On For This DTC
* Freeze Frame Priority (Value 1–15)
* MIL Fault Occurred This Trip
* Store Freeze Frame Now
* Delete Freeze Frame Now

## Fault Results

The TCM continuously checks for electrical problems, mechanical problems and
some hydraulic problems. When a problem is sensed, the TCM stores a Diagnostic
Trouble Code (DTC). Some of these codes cause the transmission to go into “Limp-In”
or “Default” mode.
The NAG 1 transmission defaults in the current gear position if a DTC is detected.
Then after a key cycle or if the transmission is placed in Park, the transmission goes
into Limp-In Mode, which is mechanical second gear. Some DTCs allow the
transmission to resume normal operation (recover) if the detected problem goes away.
A Permanent Limp-In DTC recovers when the key is cycled; but if the same DTC is
detected for three key cycles, the system does not recover and the DTC must be
cleared from the TCM with a scan tool.

## Fault Codes

|FAULT CODE|J2012 DTC|A580 DTC|DESCRIPTION OF FAULT|LIMP-IN SET|MIL LIT|TYPE OF FAILURE|
|---|---|---|---|---|---|---|
|2 |P0753| 2100| 1–2/4–5 Shift Solenoid| Yes (P)| Yes| C, E, S|
|3 |P0758 |2102| 2–3 Shift Solenoid |Yes (P) |Yes| C, E, S|
|4 |P0763 |2104| 3–4 Shift Solenoid |Yes (P) |Yes| C, E, S|
|5| P0743 |2106| TCC Solenoid Circuit |Yes (P)| Yes |C, E, S|
|6| P0748 |2107 |Modulating Pressure Solenoid Circuit |Yes (P)| Yes |C, E, S|
|7| P0778 |2108 |Shift Pressure Solenoid Circuit| Yes (P)| Yes |C, E, S |
|10| P0657| 2602| Solenoid Supply Voltage| Yes (P)| Yes| C, E, S|
|11 |P0642| 2603| Sensor Supply Voltage Low Yes (P) |Yes| C, E, S |
|78 |P0643| Sensor Supply Voltage High |Yes (P)| Yes |C, E, S |
|12| P0717 |2200 |N2 Input Speed Sensor Circuit |Yes (T)| Yes| C, E, S |
|13| P2767 |2203 |N3 Input Speed Sensor Circuit |Yes (T)| Yes| C, E, S |
|14 |P2784 |220A| Input Sensors Mismatch |Yes (T)| Yes| C, E, S, T |
|15 |P1704| 220B| N2 Sensor Overspeed |Yes (N)| Yes| C, T |
|99 |P1705|---|N3 Sensor Overspeed| Yes (N)| Yes| C, T |
|19 |P0563 |2601| System Overvoltage| Yes (T)| Yes| C, E|
|20 |P0712| 2220| Transmission Oil Temp. Sensor Shorted |No| No| C, E, S |
|21| P0562 |2600| System Undervoltage |Yes (T)| Yes| C, E |
|22| U140C |2400| CAN Right Rear Wheel Speed Signal Not Valid |No| No| C, E, S |
|23| U140B| 2401| CAN Left Rear Wheel Speed Signal Not Valid |No| No| C, E, S|
|24 |U140A| 2402 |CAN Right Front Wheel Speed Signal Not Valid |No| No| C, E, S |
|25 |U1409 |2403| CAN Left Front Wheel Speed Signal Not Valid |No| No |C, E, S |
|---| P0501 |---|Vehicle Speed Sensor Performance/Rationality |Yes (T)| Yes| C, E, S |
|26| U1400| 2405| CAN Engine TPS Message Not Valid |No| No| C, E, S |
|27 |U1404 |2406 |CAN Static Engine Torque Message Not Valid |No| No| C, E |
|28 |U1401| 240A| CAN Engine Speed Message Not Valid |No| No| C, E, S |
|29 |U1405| 2408| CAN Minimum Engine Torque Message Not Valid |No| No| C, E |
|30| U0141 |2314 |Lost Communication with Central Gateway |No| No| C, E |
|31| U1406| 2409| CAN Maximum Engine Torque Message Not Valid |No| No |C, E |
|32 |U1407 |2407 |CAN Engine Torque Demand Message Not Valid |No |No| C, E |
|33 |U1408| 2404| CAN ABS Brake Light Switch Message Not Valid |No| No |C, E|
|34| U0103| 2313| Lost Communication with Electric Gearshift Module |Yes (T) |Yes |C, E |
|35 |U0155| 2315| Lost Communication with Instrument Panel |No |No| C, E |
|36| U110B |2312 |CAN| Engine Coolant Message Missing |No| No| C, E |
|37 |U0002| 2300| Bus-Off CAN Controller 1| Yes (T)| Yes| C, E |
|38 |U0121| 2310| ABS CAN Messages Missing |Yes (T)| Yes| C, E |
|39 |U0100 |2311 |Engine CAN Messages Missing |No| Yes| C, E |
|40 |U0164| 2316| Lost Communication with A/C Control Module |No| No| C, E|
|41 |U0114| 2317| Lost Communication with CAN Transfer Case |Yes (T)| Yes| C, E|
|42| U0404 |240C| CAN Gearshift Position Message Not Valid |Yes (T) |Yes| C, E |
|43| U1402 |240B| CAN Engine Coolant Temperature Message Not Valid |No| No| C, E, S |
|44| U0414 |240D| CAN Transfer Case Message Not Valid |Yes (T) |Yes| C, E |
|48| P0602 |2010| Internal Controller Variant Not Coded |Yes (P)| Yes |C |
|49 |P0219| 2501 |Engine Overspeed| Yes (N)| Yes| C, T|
|50 |P0730 |2500| Improper Gear Ratio |Yes (N)| Yes| C, E, T |
|51| P0731 |2502| Transmission Slipping in First Gear| Yes (C)| Yes |C, T |
|100 |P0732|---| Transmission Slipping in Second Gear |Yes (C)| Yes| C, T |
|101| P0733|---| Transmission Slipping in Third Gear |Yes (C) |Yes |C, T |
|102 |P0734 |---|Transmission Slipping in Fourth Gear |Yes (C)| Yes| C, T |
|103 |P0735|---| Transmission Slipping in Fifth Gear |Yes (C)| Yes| C, T|
|52| P0742| 2510| TCC Stuck On (Mechanical) |No| No |C, E, S, T |
|53| P2783| 2511 |TCC Overtemp| No| No| T |
|54| P2638| 2520 |Torque Reduction Acknowledge Not Correct| No| No| C |
|55| P1731 |2503 |Incorrect Gear Engaged| Yes (T) |Yes |C, E, S |
|56| P1629* |2013| Solenoid Supply/Watchdog |Yes (P)| Yes| C|
|57| P1631* |2004 |Internal Controller Clock Failure |Yes (P)| Yes| C|
|58 |P1632* |2000 |Internal Controller Test Internal Watchdog Failure| Yes (P)| Yes C |
|59 |P1633*| 2002 |Internal Controller Test External Watchdog Failure| Yes (P)| Yes |C |
|60| P1634*| 2001 Internal Controller Internal Watchdog Occurred| No| Yes| C |
|61| P1636*| 2003 |Internal Controller External Watchdog Occurred |No| Yes| C |
|62 |P0604 |2005| Internal Controller RAM Failure |Yes (P)| Yes |C |
|63 |P0605 |2008 |Internal Controller ROM Failure |Yes (P)| Yes| C |
|65 |P1637| 200A| Internal Controller EEROM Failure |No| No| C|
|66 |P1638/*| 2006| Internal Controller CAN 1 RAM Failure |Yes (P)| Yes| C |
|67 |P1639/* |2007 |Internal Controller CAN 2 RAM Failure |Yes (P)| Yes| C |
|---| P0613|---|Internal Controller Failure |Yes (P)| Yes| C |
|71| P0752| 2101| 1–2/4–5 Solenoid Circuit |Yes (P) |Yes| C, E, S |
|72 |P0757| 2103| 2–3 Solenoid Circuit |Yes (P)| Yes |C, E, S |
|73 |P0762| 2105 |3–4 Solenoid Circuit| Yes (P) |Yes| C, E, S |
|74 |P0710| 2221| Temperature Sensor P/N Switch Circuit |No| No| C, E, S |
|75| P0714| 2222| Temp. Sensor Erratic| No| No| C, E, S |
|80| U1508 |2333| Electric Gearshift Module Incorrect Message Length |Yes (T)| Yes| C, E
|81| U0415| 2330| ABS Controller Incorrect Message Length |Yes (T) |Yes |C, E |
|82 |U0401| 2331 |Engine Controller Incorrect Message Length |No| Yes| C, E |
|83| U1507| 2335 |Engine Coolant Temperature Incorrect Message Length |No| No| C, E |
|84 |U0431| 2334 |Central Gateway Incorrect Message Length |No |No |C, E |
|85 |U0423 |2332| Instrument Panel Incorrect Message Length |No| No| C, E |
|86 |U0424| 2336 |A/C Controller Incorrect Message Length |No| No |C, E |
|87| U1506 |2337 |Transfer Case Controller Incorrect Message Length |Yes (T) |Yes |C, E |
|111 |U140F|---| CAN Engine Variant Message Not Valid or Missing| Yes (P)| Yes C, E |
|112| U1410 |---|CAN FCM Variant Message Not Valid or Missing |Yes (P)| Yes |C, E|

These faults also set
code P0613
(P) = Permanent Limp-In
(T) = Temporary Limp-In
(C) = Controlled Limp-In
(N) = Loss of Drive
C = Controller
E = Electrical
S = Sensor/Actuator
T = Transmission

## NORMAL TRANSMISSION OPERATION (SHIFT PATTERNS)

Normal operation of the transmission is when all upshifts and downshifts occur when
expected. The shifts should be timely and without harshness. The transmission
should be able to attain all forward and reverse gear ranges. The initial engagement
of Drive 1st and/or reverse should be prompt, without delay and smooth. There
should be no chatter during torque converter clutch operation.
The following charts provide illustration in graph form of approximately when
transmission automatic shifting should occur based on % accelerator pedal position
and transmission calculated output shaft speed (rpm).
The charts include:

* 1–2, 2–3, 3–4, 4–5 upshift patterns
* 5–4, 4–3, 3–2, 2–1 downshift patterns
* Steady state gear ranges with Open-to-Slipping (O-S) and Slipping-to-Open
(S-O) torque converter clutch operation patterns
* Fuel economy patterns
* Manual gear upshift patterns using Autostick