Hello guys, I just got a new trans in my 95 4runner. When I got it back from the shop it all worked great. It has about 50 miles on it now and the converter has stopped locking up. Everything works perfectly except for the lockup. I have tried adjusting the cable all different ways. I checked the fluid and it is at the proper level. There are no codes of any kind. I had it back to the shop and he said it is working perfectly but has no lockup and he doesnt know why. I thought I would ask you guys before he goes tearing back into it.

Thanks for any help you guys provide.

 

Hey there. that problem can be cuased by lots of things but some of the obvious to check are your brake switch, your tps sensor, or prndl switch. if its not any of those than it could be the solenoid isnt working electrically or mechanically. also check to make sure the solenoid has good powers and grounds. Youcould even try to apply power to the solinoid with a jumper wire. if it locks up than its a control problem if not its in the tranny.........

later

 

A mechanical failure of the lock up solenoid won't set off the flashing O/D light. If they replaced the solenoids then I would try replacing the lock up solenoid or at least testing it. Resistance should be 10 - 16 ohms. If it isn't the solenoid is bad.

Pickup, SC300 & 4Runner
1) Access ECT ECU. See Figs. 2 and 3. Disconnect ECT ECU
harness connector. On SC300, install check harness between ECT ECU and
harness connector. On all models, using ohmmeter, check resistance
between terminal S and body ground at ECT ECU harness connector or at
check harness. See Figs. 10 and 11.
2) Resistance should be 10-16 ohms. If resistance is okay,
replace ECT ECU. If resistance is not within specification, disconnect
electrical connector at lock-up solenoid, located on transmission
valve body. See Figs. 2 and 3.
3) Check resistance between electrical terminal on lock-up
solenoid and body ground. Replace lock-up solenoid if resistance is
not 10-16 ohms. If resistance is 10-16 ohms, check wiring between
lock-up solenoid and ECT ECU. See appropriate wiring diagram in
WIRING DIAGRAMS.
4) If wiring is okay, check performance of solenoid. See
SOLENOIDS under COMPONENT TESTS. Replace as needed. If solenoid is
functioning okay, replace ECT ECU and retest.

 

NO LOCK-UP
1) Warm engine to normal operating temperature. Connect
voltmeter between terminals TT and E1 of data link connector. See
Fig. 6.
2) Road test vehicle and ensure voltage at terminal TT is 3-7
volts in lock-up range. If voltage is correct, lock-up solenoid,
torque converter or transmission is defective.
3) If voltage is not correct, obtain access to ECT ECU.
Connect voltmeter between terminals STP and E1 on ECT ECU with
connector installed on ECT ECU. See Fig. 11.
4) No voltage should exist with brake pedal released. About
10-14 volts should exist with brake pedal depressed. If voltage is not
correct, check for defective brakelight switch or wiring circuit. If
voltage is correct, check for defective throttle position sensor or
wiring.


If you end up needing a TPS let me know cause I have two that are less than a year old.

 

Thanks guys, I hav noticed that it will lock up when you first start driving it but after about 15-20 minutes of driving it stop locking up. I also now have a code 71. And I cant get the timing set beacause short circuiting the data link connector has no effect on timing. This thing is starting to be a PITA.

 

Ok, Ive been to couple different shops and they say its the code 71 (EGR temp low) causing the TCC to not function properly. Can any of you guys provide any info on if this is possible. Also can the egr not working properly stop me from getting it to go to base timing. As of right now ive set the timing by feel but I would really like to set it correctly with a light.

 

It sounds as if the TPS is out of adjustment. It probably should have been readjusted after the trans mission was serviced. The reason I say TPS is that you can't get it to base out on the timing. Try searching for TPS on here. I know theres more than a couple threads on it. Get out a multimeter and reset the TPS and go from there.

 

I also have an EGR sensor that I'm not using. If you need it.

 

What would you want for it? Is there any way to test it to be sure its bad. I cant afford to take anymore guesses.

 

EGR GAS TEMPERATURE SENSOR
1) Remove EGR gas temperature sensor from side of EGR valve.
Place threaded end of sensor and thermometer in container of oil.
2) Attach ohmmeter to electrical terminals. Heat oil and note
resistance at specified temperature. See EGR GAS TEMPERATURE SENSOR
SPECIFICATIONS table. Replace EGR gas temperature sensor if resistance
is not within specification.
EGR GAS TEMPERATURE SENSOR SPECIFICATIONS TABLE
Temperature  F (  C) k/ohms
122 (50) ........................................... 64-97
212 (100) .......................................... 11-16
302 (150) ............................................ 2-4


Try testing it this way and let me know what you find. Although boiling oil seems a little cruel at this point. I guess the sensor will know what the normans felt like invading the english.

 

4runners also have a closed throttle switch along with the tps and if the switch is not showing closed throttle it wont go into diagnostic mode.

 

a mechanical failure will cuase the the light to flash becuase there is a sensor watching pressure in the lock up curciut. If the computer commands lockup and the sensor doesnt see that it happened mechanically then the light will flash...

 

DTC 65: NO. 4 SOLENOID CIRCUIT (PICKUP & 4RUNNER WITH A-340H)
NOTE: A stuck solenoid will not set a trouble code. Trouble codes
are only set for circuit malfunctions, not mechanical
failures.

 

im a transmission tech and build them all day and i will guarantee that a mechanical failure will set a code depending on the conditions. There are curciut codes also but they are different from other codes for example a ratio error code with the fualt imediatly after a shift code always means a bad clutch pack. or if the cvi displays are out of spec it will set a code also witch means excessive clutch clearance. or if you get a transmission temp code it can be cuased by a plugged cooler. or even a turbine or output speed sensor code can be cuased by slipping clutch which will put the trans into limp in mode. Almost all electronic transmissions have a way of verifying that the transmission performed the task that the ecu commanded for all shifts lock-up etc.... im not saying that babypig's tests are wrong but dont always rule out a mechanical failure. in your case its probably the other code giving te hassle. toyotas have wierd warm-up mapping like 2000 rpm max shift poit when cold and lock-up inhibition. so if the tcu thinks the cars cold or too hot it wont lock up (for ex.) I dont want to step on any toes so jus take all of our info and filter it out as needed. Hope u get ur trans figured out(probably simple fix) like the egr temp sens.

 

I have got the code 71 figured out and eliminated. But the trans still didnt lock up.
As I said earlier in this thread the trans will lock up when cold, but not when warm. It is -2 degrees out right now and I just got home, The converter was locking up even after driving for over an hour. I got out and put my hand on the pan and it was barley warm.

A couple days ago it was in the 40s and it was not locking up. So I got on the interstate and drove it at a constant 65mph to try and get the light to flash so I could get a code. I drove for about ten miles and no code. It was not locked up at any point in that ten miles. I dont understand why im not getting a code. Somthing (eletronic OR mechanical) is not working. As of right now im leaning towards the mechanical part. If somthing electronic has went bad I "should" have a code.

 

sometimes it wont give acode becuase whatever part thats malfunctioning is working but not within spec like for example.. when its in lockup and you step on the brakes it will imediatly come out of lockup so if the cumputer saw that yuor brakes where on at all times even if they werent physically applied(becuase of a fualty brake switch) or broken wire it would just never lockup leaving no code becuase thats what it is design to do. There are many different things that can cuase the failure but no code. The best thing to do is watch some data on a scan tool and see what the computer is seeing. although toyota automatics dont provide much datastream some components would have to be tested manually. But always make sure and rule out a control issue before you suspect mechanical fualt because these transmissions are usually trouble free. I woud suspect a control problem unless the flud is burnt or there is something in the pan.... good luck

 

Is there any kind of temperature sensor in the trans? I ask because it ALWAYS goes into lockup when the trans is cold.

 

There is a housing behind the intake that has three or four sensors on it. That is where it is located. I'm looking for a diagram of which one it is in the factory service manual. I'll post it when i find it.