Number9

Thanks again. This answers my questions. One last question is can a faulty ECU be the cause of the fault. My transmission guys said they checked the circuit and solenoid and everything checked out. They are not familiar with Land Rover. This is why I am going to check the circuit. Thanks again.

 

Much depends upon the knowledge and thoroughness of your guy's/checks. EAT/ECU could cause fault and would be easy to swap out for troubleshooting if a spare is available. Some of info referenced was from manual linked below, our trans start at p. 27. Good luck.

https://www.google.com/url?sa=t&rct=...BdIhLsom8SD0bg
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I checked the coil resistance and read 40 ohms. Then applied 12 V to the solenoid circuit with truck in drive and foot on the break and the engine rpm dropped when the voltage was applied. Got another ecu, connected the new ecu and still getting a lockup clutch monitoring error. On the real time output the M3 valve goes from open to opening at about 40-50 mph. Any suggestions. Do i need to get a dealer to read the errors. I try to avoid dealer visits $$$$.

 

LU should occur earlier unless you have a heavy foot. Found a better reference for when LR TC LU for 3rd/4th occurs and may help. With slight throttle/acceleration I can now easily see mine using tach LU 4th about 35 MPH.Assume you are clearing codes with your reader. Do codes or pending ones and eng light come back immediately or after a few drive cycles? Was solenoid resistance check made at trans pug or elsewhere? No idea how sensitive the trans ECU is to +5.5 ohm and apparently your code is for open circuit?

Since your last reply I was able to change my trans fluid/filter, noticed LU now at lower MPH & RPM. First change since purchase and besides being dirty it was low on fluid also. Quantity, being new or both improved the LU. With a recent TC change your fluid should be clean but you may want to ensure it's serviced to the proper level and check condition.

What code # are you reading? No clue here of what codes if any what a dealer could read than you can't.
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number9

It takes a few drive cycles before the check engine light comes on. I checked the solenoid from the connector at the TCU. The code reader displays' a message that reads Lock-up clutch monitoring. Could this be a fault with the lockup clutch in the torque converter. I hope not. This is a rebuilt converter purchased last April.

 

Reader gives an interpretation of the code rather that a P0741, LU detection or P0743, LU solenoid circuit as a normal scanner does? Lock-up clutch monitoring is probable from first code so probably not the circuit detection code. Many of the code lists floating around from the scanner/reader makers leave much to be desired compared to the vehicle mfg. tech manual info.

You haven't given a definitive answer to that yet. Forget my exact rpm drop but 200 to 300 and easy to detect once at operating temp. Getting only a slight drop might indicate a slipping TC clutch and no drop indicate LU valve not opening to allow fluid to clutch. Believe either one of those could give P0741.
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i can check out the engine rpm at 50 mph with my reader (iCarsoft) in real time. This is when the mv3 solenoid changes from open to opening. The solenoid worked when a external voltage was applied directly through the TCM connector.

 

Saw that earlier and don't understand the open to opening part of statement? Looking at a meter or reader? Thanks.
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My diagnostic scan tool in real time for the M3 valve displays the word open. Then goes to from open to opening at about 50 mph. I connected a DVM to pin 32 to monitor the voltage. Voltage was 13.5 volts. When the real time M3 valve monitor went from open to opening, the voltage dropped to .3 volts. I believe this is and indication that the lock-up solenoid is working. This seems like the torque converter lock-up clutch problem. I am going to check with my guy and see what the he thinks.

 

Good to know voltage drop reading as thinking you'd see.

That's not telling you solenoid is working/opening, only that the solenoid coil is providing a path to gnd. So no RPM drop or actual lock-up? Could be the LU solenoid is stuck in closed position and relatively easy R&R. Let know what your guy thinks.

Since you seem to be getting LU command signal late your output shaft speed sensor may be on the fritz.
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