padavid123

I have a 2000 GC. The check engine light came on. I scanned it and got P0740. TCC Solenoid. The transmission works fine. I replaced the TCC Solenoid and cleared the code. After a couple days driving, the light is back on with the same code. Everything works fine. What to do now. David

tsconver

Did you use a mopar selonoid or a parts store one? Sometimes it makes a difference. You could have gotten a bad one, maybe a bad torque converter, you change your fluid and filter, maybe pressure to low to get a lockup? Maybe a bad wriing harness?

padavid123

Did use a Mopar part, replaced the filter. Transmission has no indication of a problem. Runs nice and smooth. Also, when checking the fluid level, one side of the stick will have fluid strung out to the full mark but the other side will have a lower level more consistant with the way an oil dipstick would look. Which side should I use to determine correct level? David

tsconver

Are you parking level when checking the oil? Did you ctcle it through all of teh geras? I go to low then to 2nd then to drive, then to reverse, then to neutral and check the oil with it in neutral. My level is pretty consistent on both sides when I check it. It is important to be in neutrakl, have it warmed up and have cycled teh trans through the gears.

YOu have three options, try a new selenoid, get an ohm meter and a FSM and check all of the wiring, or take it to a dealer and say fix it. I guess a fourth choise would be to replace the TCM.

By the way do you have a I6 or V8?

Here is teh 02/03 FSM Troubleshooting for P0740

When Monitored and Set Condition:
P0740-TORQUE CONVERTER CLUTCH CONTROL CIRCUIT
When Monitored: During Electronically Modulated Converter Clutch (EMCC) Operation.
Set Condition: Transmission must be in EMCC, with input speed > than 1750 RPM.
TCC-L/R Solenoid achieves the maximum duty cycle and can not pull engine speed within
60 RPM of input speed. Also when the transmission is in FEMCC and the engine slips TCC
> than 100 RPM for 10 seconds. This DTC can take up to five minutes of problem
identification before illuminating the MIL.
POSSIBLE CAUSES
RELATED DTC P0750 PRESENT
INTERNAL TRANSMISSION
TRANSMISSION SOLENOID/TRS ASSEMBLY
INTERMITTENT WIRING AND CONNECTORS
TEST ACTION APPLICABILITY
1 NOTE: Low fluid level can be the cause of many transmission problems. If
the fluid level is low locate and repair the leak then check and adjust the
fluid level per the Service Information.
NOTE: Always perform diagnostics with a fully charged battery to avoid
false symptoms.
With the DRBIIIt, read the engine DTC’s. Check and repair all engine DTC’s prior
to performing transmission symptom diagnostics.
With the DRBIIIt, read Transmission DTC’s. Record all DTC’s and 1 Trip Failures.
NOTE: Diagnose 1 Trip Failures as a fully matured DTC.
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors.
Repair as necessary.
Perform the Shift Lever Position Test. If the test does not pass, refer to Symptom test
for P0706 Check Shifter Signal.
For Gear Ratio DTC’s, check and record all CVI’s.
Most DTC’s set on start up but some must be set by driving the vehicle such that all
diagnostic monitors have run.
NOTE: Verify the flash level of the transmission controller. Some problems
are corrected by software upgrades to the transmission controller.
NOTE: Check for applicable TSB’s related to the problem.
Perform this procedure prior to Symptom diagnosis.
All
Continue
Go To 2
88
TRANSMISSION - RFE
TEST ACTION APPLICABILITY
2 With the DRBIIIt, read transmission DTC’s.
Is the DTC P0750 present?
All
Yes ! Refer to the Transmission category and perform the appropriate
symptom.
Perform 45RFE/545RFE TRANSMISSION VERIFICATION
TEST - VER 1.
No ! Go To 3
3 With the DRBIIIt, Read and RECORD ALL Transmission DTC’s. After recording
DTC’s, erase DTC’s.
Drive the vehicle until the transmission temperature is at least 43°C or 110°F.
Perform the following steps 3 times.
Drive the vehicle at 80 km/h or 50 MPH.
Allow 4th gear to engage for at least 10 seconds.
Close the Throttle.
Tip back into the throttle until the TPS angle is between 25 and 29 degrees.
NOTE: If the throttle angle goes over 30 degrees, you must close the throttle
and try again.
Did the TCC engage (Engine speed approximately equal to input speed) during any
of the attempts?
All
Yes ! Go To 4
No ! Go To 5
4 The conditions necessary to set this DTC are not present at this time.
Using the schematics as a guide, inspect the wiring and connectors specific to this
circuit.
Wiggle the wires while checking for shorts and open circuits.
With the DRBIIIt, check the EATX EVENT DATA to help identify the conditions in
which the DTC was set.
Were there any problems found?
All
Yes ! Repair as necessary.
Perform 45RFE/545RFE TRANSMISSION VERIFICATION
TEST - VER 1.
No ! Test Complete.
5 With the DRBIIIt, check for other transmission DTC’s.
Are the DTCs P1775 and P0841 present also?
All
Yes ! Replace the Transmission Solenoid/TRS Assembly per the Service
Information.
Perform 45RFE/545RFE TRANSMISSION VERIFICATION
TEST - VER 1.
No ! Go To 6
6 If there are no possible causes remaining, view repair. All
Repair
Repair internal transmission per the Service Information. Inspect
the Primary Oil Pump and replace if necessary. If no problems are
found in the Oil Pump, replace the Transmission Solenoid/TRS
Assembly. Replace the Torque Converter in either case.
Perform 45RFE/545RFE TRANSMISSION VERIFICATION
TEST - VER 1.

padavid123

WOW!!!!! I did well just to replace the TCC solenoid. I will double check the wiring. On the fluid check, I did as you recommended. When I replaced the solenoid, I put in a new filter and 5 quarts of ATF+4. It appeared that this was sufficient to put the level. The MIL light took a couple days to come on. I read somewhere that the amount of fluid should be somewhere between 5 & 6 quarts. I have since increased the fluid to where it is just below the last hole on the stick (the side that shows the most amount of fluid). I am hoping that being a little low on fluid may have tripped the light. I did speak to a dealer, prior to installing the new solenoid, and the d/ealer told me that if the transmission was working fine, they might need to "flash the computor". I just have one of those pocket scanner/eraser units. Again, thanks for your help. I have the 4.0 engine and the car now has 110K miles. David

tsconver

LOL yeah it is a pretty in depth troubleshooting. I tend to leave trannies to the pros, at least auto ones, manuals are pretty easy to work on, but autos are a whole nother story, GL with your issue, let us know if you figure it out and what it was or took to fix.

ebarnett

Hey guys...I've been using my moms grand cherokee to commute to and from work. It is idling rough and the check engine light has been on...Just took it by autozone real quick to see if it might have been something simple. Showed the Torque converter clutch as the supposed problem. but says it could be low fuel level, bad TCC, poor fluid quality or internal tranny failure...How do I check to rule out some of these?

Durango323

How much did you pay to get it fixed? Or did you do it yourself? I have the same problem with my 99 GC.. Lemme know Asap Plz

Rapperfox

I just replaced our solenoid and governor switch, replaced the filter and gasket and we are still getting the code.

I have not checked the wiring, I'm wishing I did because I've dropped the pan twice now.

What's this about the dealers flashing the computer?!

Appreesh.

Rapperfox

O.k, I called my local dealership and they said that upgrading my computer (flashing) might be the problem. $95.00


This just sounds right to me. I feel pretty confident that my trans is working beautifully. This fix just seems to make sense. Can anyone please, tell me I'm wrong before I do it?

Apreesh.

elwoodblues

Thread revival, but did any of these fixes work? I have the exact some situation. Replaced the solenoids and still getting the code. The TC locks and unlocks normally.

dave1123

Same here guys. My P0740 code sets about every month or AFTER I run a long distance on the highway. I haven't replaced the solenoid yet because a good trans shop said it could be the solenoid or the torque converter clutch or something else and it was operating fine. That was 3 years ago. Every so often, I clear the code with a scan tool and it stays off for a long time, then resets. The only thing different about the way it works is when you let off on the throttle, the rpms drop about 200 where if the clutch is engaged, it won't. I don't care, I just drive it. When it needs to be inspected, I just clear the code the day before. It doesn't seem to be a problem with fuel mileage either.

I did have my computer reflashed on a recall, BTW. It didn't change anything.

elwoodblues

Got my codes read again today and this one came on (in addition to the P0700 and P0740). According to this site, P0740 - OBD-II Trouble Code
the coolant temp sensor can trigger the P0740. I thought this might be worth investigating as I don't have any symptoms. Any ideas? Thanks!

dave1123

Now that's interesting. The TCM DOES take trans temperature into account when turning on the TCC. It also doesn't let it shift into 4th (O/D) when it's below 32*F or above 260*F.

Reading thru the trans manual, there is a TCC relay as well, but IDK where it is.