Thread: Auto trans limp mode

Hi, i dunno where you've got those instructions from as this P0722 code according to ZF(LR too) means only one thing: that the torque converter slipping" so i can't see how you can rule this out by checking continuity or resistance. I'm affraid the only fix for you is to replace the TC

Has it had any recent work done on it?

Originally Posted by sierrafery

Hi, i dunno where you've got those instructions from as this P0722 code according to ZF(LR too) means only one thing: that the torque converter slipping" so i can't see how you can rule this out by checking continuity or resistance. I'm affraid the only fix for you is to replace the TC

Hi I followed from below

DTC P0722
Stall speed monitoring.
Possible causes by suggested order of priority:
Connectors C243,EAT C193.
Open circuit shaft speed sensorC193/14 ( to C193/42 (R).
Open circuit C243/E (K) to C193/42 (R).
Open circuit C243/F ( to C193/14 (.
Shaft speed electrical interference.
Shaft speed sensor fault.
Torque converter mechanical fault.
Connectors C243,EAT C193.
CONNECTOR
Check for connector not correctly latched, backed out pins, damaged pins, corroded pins.
Open Circuit Shaft Speed SensorC193/14 ( To C193/42 (R).
OPEN_CIRCUIT
Check resistance > 1M Ohm
Open Circuit C243/E (K) To C193/42 (R).
OPEN_CIRCUIT
Check resistance > 1M Ohm
Open Circuit C243/F ( To C193/14 (.
OPEN_CIRCUIT
Check resistance > 1M Ohm
Shaft Speed Electrical Interference.
Use Live Data reading to display the output shaft speed as measured by the transmission ECU. CHECK THE
FOLLOWING:
With the engine running and the position switch in 'P' the shaft speed should measure 0 RPM .
If the reading is not 0 RPM then there may be a problem with electrical interference.
Check the connections to the screen around the output shaft sensor wiring. POSSIBLE FAULTS
Faulty output shaft sensor wiring.
Faulty output shaft sensor.
Shaft Speed Sensor Fault.
Use Live Data reading to display the output shaft speed as measured by the transmission ECU. CHECK THE
FOLLOWING:
Monitor the road speed (from the vehicle speedometer) and the output shaft speed while driving on the road
or on a rolling road.
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The two readings should maintain the same ratio. If one reading doubles so should the other reading.
If the readings do not maintain a 􀀁xed ratio the output shaft sensor may be faulty. POSSIBLE FAULTS
Faulty output shaft sensor
Torque Converter Mechanical Fault.
Use Live Data reading to display the output shaft speed as measured by the transmission ECU. CHECK THE
FOLLOWING:
Monitor the road speed (from the vehicle speedometer) and the output shaft speed while driving on the road
or on a rolling road.
The two readings should maintain the same ratio. If one reading doubles so should the other reading.
If the readings maintain a 􀀁xed ratio the torque converter may be faulty. POSSIBLE FAULTS
Transmission torque converter mechanical fault.

Originally Posted by discorevy

Has it had any recent work done on it?

Hi Discovery

No recent work done that I can think is related. The symptoms used to be now and again but now is constant

A stall test showed holding just under 2800 rpm at normal operating temp. It is most likely the TC but need to resolve the electrical test first.

I have also removed the PTO cover to make sure the output shaft bolt was tight just in case the speed sensor ring was loose, all good there.


I do wonder if rave has the procedure detail wrong because if i reverse test for continuity ie C243/E to C193/42 instead test pin C193/14 I get a reading.

thanks in advance

Originally Posted by thai_tiger

Hi I followed from below

DTC P0722
Stall speed monitoring.
Possible causes by suggested order of priority:
.........................

Sorry, i stand corrected as reading those instructions i can find logic in them so would be good to check those live readings then

Originally Posted by sierrafery

Sorry, i stand corrected as reading those instructions i can find logic in them so would be good to check those live readings then

Thats ok np

Can you suggest where to look as I can not get reading after plug from transmission loom


"Open circuit C243/E to C193/42 but if I check at the connector behind window switch panel where the transmission loom comes through the floor I have continuity ...all good"

Originally Posted by thai_tiger

I do wonder if rave has the procedure detail wrong because if i reverse test for continuity ie C243/E to C193/42 instead test pin C193/14 I get a reading.

Unfortunately there can be all kind of mistakes in RAVE, i found them not once in many cases, in this case according to the diagram there should be continuity between C243E to C193/42 and C243F to C193/14 if the diagram is not wong but IMO if you get E to 14 and F to 42 maybe the diagram is wrong

Originally Posted by thai_tiger

Thats ok np

Can you suggest where to look as I can not get reading after plug from transmission loom


"Open circuit C243/E to C193/42 but if I check at the connector behind window switch panel where the transmission loom comes through the floor I have continuity ...all good"

you get continuity from the console(C0678/0728) toward 193/42 or toward 243/E? you should check from the console toward both sides