If the transmission controller senses a problem in the system a fault code will be triggered and stored in memory.  These codes will stay in memory until either a technician clears them or they are displaced by newer codes being stored.

Codes that will cause the transmission to go into limp in mode.

11, 13, 14, 15, 16, 17, 18, 20, 21, 22, 23,  24, 25, 26, 27, 31, 32, 33, 39, 41, 42, 43, 44

The following codes will not cause the transaxle to go into limp in mode.

12, 19, 28, 29, 37, 38, 45, 46

The only way the codes can be pulled from the computer is with the DRBII scan tool.  If you have a shop that is nice enough to give you a printout of the codes, a friend with a scanner, or access to one you can decipher these codes below for a better understanding as to what may be going on.

Note:  Each one of these codes is a specific test before start up for the controller. When the controller fails
the test or doesn't match up to known information these codes are set. Each of the codes calls for replacement
of the controller when they are set. These are not commonly seen codes.

Code 12 - Battery was disconnected

Note:  This code is provided, as reference information to tell you that battery voltage was lost to the
controller.

Code 14 - ETAX relay always on.

Note:  The controller shut down voltage to the etax relay. When it checked pins 16 and 17 on the controller
(to see if the points opened in relay) it saw more than 3 volts present.

Diagnostic Tip
To check for welded points switch the etax relay with the back up light rely.

Relay Locations
On controller body
Passengers side fender well
Driver's side fuse box

Other Causes
Short to ground in SA1 circuit
Open in SA1 circuit between relay and ground
Open in SF1 circuit between relay and ground
Open in J91 circuit from relay to ground
Open in J11 circuit from relay to splice
60 pin connector problem (pins 15,16,17)
Bad controller

Code 15 - ETAX relay always off

Note:  Controller commanded etax relay to energize (provide voltage to solenoid block). When it checked
pins 16 and 17 for 12 volts it saw less then 3 volts present.

Diagnostic Tip
To check for welded points switch the etax relay with the back up light rely.

Relay Locations
On controller body
Passengers side fender well
Driver's side fuse box

Other Causes
Short to ground in SA1 circuit
Open in SA1 circuit between relay and ground
Open in SF1 circuit between relay and ground
Open in J91 circuit from relay to ground
Open in J11 circuit from relay to splice
60 pin connector problem (pins 15,16,17)
Bad controller

Code 18 - Engine speed signal circuit

Note:  Transmission controller is not receiving information it needs from the engine controller.

Diagnostic Tip
Check to see if the wrong computer is installed on the vehicle.

Other Causes
Open or short in N7 circuit - distributor pick up signal
Bad sensor in distributor
60 pin connector problem (pin 45)

Code 19 - CD2 bus communication

Note:  Transmission controller is not receiving information it needs from the engine controller.

Diagnostic Tip
Check for opens or shorts between
Pin 46 (engine controller) and pin 4 (transmission controller)
Pin 26 (engine controller) and 43 (transmission controller)

Other Causes
Bad engine controller
Bad transmission controller

Code 20 - Switched battery

Note:  When the controller checked pins 16 and 17 it saw less then 3 volts (this confirms that the etax relay
is open). However, when it checked the solenoid pack pressure switches it saw voltage. This sets code 20.
This is not a common code.

Other Causes
Bad etax relay (welded points) with a open
SF1 circuit between controller and splice
Intermittent short to battery on SF1 circuit
Bad relay with an intermittent problem
Bad controller

Code 21 to 27 - Pressure switch circuits
   21 - OD
   22 - 2/4
   23 - 2/4 and OD
   24 - L/R
   25 - L/R AND OD
   26 - L/R AND 2/4
   27 - All Pressure Switches

Note:  When the controller checked the status of the pressure switches they were either opened or closed at
the wrong time.

Causes

1. - If you rebuilt or installed a rebuilt solenoid block with new switch rubbers chances are the rubber
seals are too big setting these codes. To confirm this install a used solenoid block (not rebuilt). If the
vehicle now works the seals were the problem.

2. - The 2nd most common cause of these codes is loose fitting female connector pins in the solenoid
harness.

Here's How To Check Them
A. - Get a # 43 / .089'' drill bit
B. - Insert drill bit into each of the female pins. Drill bit must have some drag when installed and
removed.

Here's How To Fix Them
A. - Insert # 43 drill bit into female pin. B. - Use a very small needle nose or screwdriver and
squeeze the pin down against the drill bit. C. - Test for drag.

3. - The 3rd most common problem is opens or shorts.

Here's How To Check For Them
A. - Unplug solenoid 8 pin connector and controller 60 pin connector.
B. - Use an ohm meter to check between these wires for opens or shorts.
Solenoid pin 2 to controller pin 50 (Low/Rev)
Solenoid pin 1 to controller pin 57 (2/4)
Solenoid pin 1 to controller pin 9 (OD)

Note:  If none of the wires checked are opened or shorted then the controller is bad. This is very
uncommon.

Code 28 - Check PRNDL signal

Note:  When the controller checked the status of the PRNDL or NSS switch they were either opened or
closed at the wrong time.

1. Check for loose fitting pins on PRNDL/NSS switches or PRNDL/NSS connector end
2. Check for opens or shorts in wires between PRNDL/NSS and controller.
3. Install new PRNDL/NSS switches one at a time

Code 29 - TPS signal

Note:  Transmission controller sees TPS out of range or intermittent signal

Diagnostic Tip
Try clearing code from transmission controller. Here's why.   If TPS was replaced at a general repair
shop they might only have cleared the code in the engine controller.  If you cleared the code and it came back ,
then hook the scanner up to the engine diagnostic connector ( in engine compartment ) and see if it shows code 29.
Yes = bad TPS
No = open or short in wiring between engine and transmission controllers.

Code 31 to 33 Pressure switch problem
   31 - OD
   32 - 2/4
   33 - OD and 2/4

Note:  These codes are similar to codes 21 to 27 in that the controller has seen the pressure switches
opened or closed at the wrong time. The difference is codes 31 to 33 indicate solenoid block or
internal transmission problems only - no electrical problems.

Diagnostic Tip
If you rebuilt or installed a rebuilt solenoid block with new switch rubbers chances are the rubber
seals are too big setting these codes. To confirm this install a used solenoid block (not rebuilt If the
vehicle now works the seals were the problem

Can be worn out accumulator bores (loss of oil pressure to switches) or warped lower channel
casting in valve body causing switches to apply at wrong time.

Important
Always check accumulator bores for wear and flat sand/stone valve body to prevent these problem codes.

Code 36 - Fault immediately after shift

Super Important
ANYTIME this code appears with any of the 50 series codes it tells you there is NO electrical
problem! That means, there is a hydraulic or mechanical problem inside the transmission.
  Broken UD/OD snap ring
  Burnt out OD clutch pack
  Gear train failure

Code 37 - Solenoid switch valve stuck (stuck in L/U position)

Note:  The controller sees the SSV stuck in the L/U position in the valve body.

Diagnostic Tip
This code is usually only seen after overhaul. The condition you will get is no 1st after a upshift.
Vehicle will take off in 2nd gear and upshift. Do not confuse this with fail-safe (2nd and reverse only).

There are only 2 things that that will cause this valve to stick.
1. - Over tightening valve body (impact wrench)
2. - Dirt or debris causing restricted cooler (cooler not flushed)

Code 38 Lockup control

Note:  When controller called for lockup it saw a slip or no lockup at all.

Diagnostic Tip
This code is usually set after a overhaul and has 3 possible causes

1. - Pump Wear - Any amount of wear in the pump pocket between suction and discharge will cause
low pressures to the lockup apply surface of the converter clutch.

2. - Torque Converter - A poor quality rebuilt will cause slippage of the converter clutch.

3. - Solenoid switch valve stuck in L/R position in the valve body causing no lockup.

The problem is most often the pump. Next is the torque converter. Last is the SSV valve stuck in the
valve body.

Important
Most shops when they encounter code 38 replace both the pump and the torque converter
at the same time to avoid a 3rd R and R.

Code 39 - Gear ratio error (1989 and 1990 only)

Note:  This code says the controller is seeing a slip.

Diagnostic Tip
If the code is intermittent chances are you have a bad connection at the input or output speed sensors
caused by loose fitting female pins in the wiring ends. Do not attempt to resize the female ends in the
connector. Replace the wiring ends with Chrysler kit part # 4419478.

Input or output sensors can set code 39 (but, usually don't). If you want to verify if the sensors are
setting the code then change them one at a time, clear the code and test drive.

If code 39 is not intermittent (and goes to limp in mode at the same mph every time - slipping clutch)
it is a internal transmission problem with 2 possibilities.
Before overhaul - broken OD pressure plate tapered snap ring or burned OD clutches in input drum.
After overhaul - misassemble of input drum (OD frictions/snap rings/seals).

Code 41 to 44 - Solenoid circuit error
   41- L/R
   42- 2/4
   43 - OD
   44 - UD

Note:  The controller has seen an electrical problem when it tested the solenoid circuit.

Diagnostic Tip
These codes are usually set by:
Opens or shorts in wiring between solenoid pack and controller.
Solenoid or controller connections
Bad controller
Solenoid pack

Code 46  3-4 shift abort

Note:  The controller saw too long of a input speed change on the 3-4 upshift.

Diagnostic Tip
When this happens the vehicle will usually try to make the 3 - 4 shift but go right back to 3rd.  It feels
like it's going in and out 3 -4 / 4 -3 / 3 -4 / 4 - 3. There are 2 causes.

Before overhaul - broken OD pressure plate snap ring or burned OD friction.
After overhaul - misassembled input drum /OD clutch/snap rings/ seals.

Code 47 - Solenoid switch valve (stuck in Low/Rev position)

Note:  The computer sees the SSV stuck in the downshifted position.

Diagnostic Tip
This code is usually seen after overhaul tightening VB with an impact or dirt from cooler not being flushed.

Code 50 to 55 - Speed error
   50 - Speed error in Reverse
   51 - Speed error in 1st
   52 - Speed error in 2nd
   53 - Speed error in 3rd
   54 - Speed error in 4th
   55 - Speed error in Neutral 9 (for future use)

Note:  When these codes set the controller has either seen the wrong gear ratio for a particular gear or an
excessive change in turbine or output shaft speeds.

Super Important
If code 36 is present (fault immediately after shift) with one of these 50 series codes there is a internal
transmission problem!
  UD/OD snap ring broken
  OD clutch pack burnt up
  Gear train failure
  etc.

Code 56 - Turbine speed sensor error
Code 57 - Output speed sensor error

Note:  Controller has seen an excessive change in turbine or output rpm in any gear.

Diagnostic Tip
If the code is intermittent chances are you have a bad connection at the input or output speed sensors caused by
loose fitting female pins in the wiring ends. Do not attempt to resize the female ends in the connector. Replace the
wiring ends with Chrysler kit part # 4419478.  Input or output sensors can set code 39 (but, usually don't). If you want to verify if the sensors are setting the code then change them one at a time, clear the code and test drive.

Code 60 to 63 - Inadequate clutch volume index - CVI's (1990 and up)
   60 - L/R
   61 - 2/4
   62 - OD
   63 - UD

Note:  The controller has seen too low or too high of a CVI to apply a clutch. CVI is the amount of time it
takes for a clutch to go to 0 clearance measured in CC's

Diagnostic Tip
CVI codes can be set by any of the following
Broken OD pressure plate tapered snap ring
Clutch packs misassembled or set too tight
Misassembled accumulators
Worn accumulator bores
Leaking accumulator seals