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'96 Tracker. Automatic torque converter clutch fault codecode

14K views 31 replies 7 participants last post by  Bex  
#1 ·
This tracker has got the 3spd automatic and my son tells me that there's a code for the torque converter clutch and another for the EGR. The EGR should be an easy fix but I don't know much about the automatic transmission having never had an auto in a tracker before. I'm looking fror a bit of an education on this clutch. I'll certainly check out the wiring before I get any deeper but what exactly is this clutch thingy? The car drives and shifts gears fine. Is this a locking clutch to prevent torque converter slippage at speed? There is an immediate increase in engine RPM when I press the accelerator at 60MPH -- no sign that there is a locked torque converter. Is this clutch accessible while the transmission is installed? Any information you can share about this would be handy. As a '96, its the first year of OBD2 and all of the diagrams I have indicate wiring for a 4spd automatic instead of the 3spd that I have. There is no overdrive button in the car. My guess is that '96 is a transition year.
 
#2 ·
The 3 speed TC clutch lock-up is very basic. IIRC an ECU signal to a relay that energizes a solenoid INSIDE the transmission that sends pressure to the clutch.

For info on US market TracKicks:

Until the 1999 MY (model year) body change, 2 door trackers/sidekicks with automatics only came with 3 speed non-computer controlled transmissions. NO OVERDRIVE.

-AND-

Other than the VERY first four doors, ALL 4 door automatic TracKicks came with the 4 speed computer controlled OVERDRIVE transmissions.
 
#3 ·
There are electrical diagrams for the 3 speed tranny over on Acks FAQS - the 96 came with both a 3 or 4 speed. Make sure you follow for info for the 3L30 tranny:
http://acksfaq.com/2016bp.php?urlname=http://www.acksfaq.com/HTML/trackerfsm.htm

And while the TCC code in the 96 will be different from the earlier models (where I don't think they throw a code) there are some tests for the relay from the earlier FSM's that may help, below.
 
#5 ·
If you are getting a code, then your fault is normally electronic/electrical, as the ECU is getting its information via wires, sensors, relays, etc. Good luck.
 
#6 ·
Monitoring, the TCC relay wire to the transmission at the relay, I get 12.6V to the wire that goes to the transmission at around 50MPH. There are two wires on the transmission connector. I can't get to the connector on the transmission because the catalytic converter is in the way but the connector looks okay. The TCC is not engaging. I found another post about this and it reads as though the TCC solenoid is replaceable by removing the pan. Is this true? My autoparts store sells a solenoid for $70. This is a daily driver. Is it a fair shot that I should just order a solenoid and pan gasket?
 
#7 ·
Monitoring, the TCC relay wire to the transmission at the relay, I get 12.6V to the wire that goes to the transmission at around 50MPH. There are two wires on the transmission connector. I can't get to the connector on the transmission because the catalytic converter is in the way but the connector looks okay. The TCC is not engaging. I found another post about this and it reads as though the TCC solenoid is replaceable by removing the pan. Is this true? My autoparts store sells a solenoid for $70. This is a daily driver. Is it a fair shot that I should just order a solenoid and pan gasket?

How does the ECM know that the TCC engages? What is the monitoring method? Does anyone know of a way to fool the ECM? My guess is that is has to deal with the second wire on the transmission connector. I have 5 days left to get the car inspected at the state inspection station.
 
#8 ·
The ECU provides the ground to the TCC relay. Did you do any of the FSM tests??? The TCC relay is in the engine bay, just by the fusible link box (the fuse box on the panel near the battery. You don't have to get near the tranny to test it.
 
#9 ·
I've found the relay and I've put a voltmeter on the white wire that goes to the transmission. The voltage to the transmission at the relay goes from 0 to 12.6V at about 50MPH. It also drops back to zero when the brake pedal is pressed just like it should and pops back up to 12.6V when I let off the brake as long as I'm still above 50MPH so the ECM is working and so is the relay. What does the ECM monitor to display a P0740 fault code? In other words, what is the ECM looking at to determine that the TCC is not working? I have verified that the ECM is applying ground to the relay and that the relay is working. What is being monitored? -- the second wire from the tranmission?? -- What is supposed to happen on this wire?
 
#12 ·
.... I have verified that the ECM is applying ground to the relay and that the relay is working. What is being monitored? -- the second wire from the tranmission?? -- What is supposed to happen on this wire?
I have looked in my 1998 Tracker manual at the diagrams and procedures and really can not find any answer. (it has nice pictures and stuff... just not the answer to your question.)

I did try and find the same diagrams/procedures in Acks FAQS (for a 1996 Tracker) but found the section referred to in the manual (7A-11B ) is not on his site. I have ran out of time for today. :eek:

My repair manual indicates that the second wire from the transmission is not used which must be an error.
What manual do you have?
 
#11 ·
If you're using a Haynes or Chilton's manual, there's a lot of incorrect information, you'd be better served with a factory service manual (FSM).
 
#13 ·
I've got the Haynes manual (#90010). The diagram is probably okay for the 3spd auto with OBD1 which does not monitor the TCC.
What do people do if they convert to a manual transmission to prevent the code? The car drives fine and my commute is 55mph and under.

I could spring for a new solenoid (not the relay) if the solenoid resides under the transmission pan -- not a big deal. A solenoid, gasket, and new filter would be under $100 but I haven't got a confirmation by anyone that the solenoid is replaceable with the tranny still in the car. Or,... some sort of bypass for the ECU monitoring circuit would be okay as a way to make make the car legal while I figure this out. I haven't read anything about the monitoring circuit looking for a drop in engine RPM. My guess is that it wants some sort of voltage on the second wire coming out of the tranny.
 
#19 ·
I've got the Haynes manual (#90010). ...
Both the Haynes and the Cliton's manuals suffer from the same thing, they try and cover too much in too little space. The results are poor at best. Look at the list of rigs covered and the years. Look at the size of the manual. Most will say to throw it in the trash.

The correct manual for your car, the factory maintenance manual (FSM) is three volumes... EACH thicker than the Haynes.

I have a set of 1996 Tracker Manuals around.... somewhere. I'll find them and look if there is more info. The 1998 manual only has a diagram very much like what is here and several pages of troubleshooting procedures. A quick look at what you have done and compared to this list, puts you at: "Replace PCM with known good PCM and retest." (The ECU was changed to PCM in 1997.)

But I only had a few minutes... gone now :eek:
 
#15 ·
How about this diagram, shows the unused wire.
Can I assume if you tested pin A to ground you would measure the coil or would the diode mess up the results. May be you test it either polarity (leads either way around) you should get almost the same results meaning the coil is not open circuit.

Image
 
#16 ·
This diagram seems to show the correct info but it doesn't show where the other wire from the tranny goes -- probably goes to the ECU. From the relay, it is a white wire that goes to the transmission and its the one that has 12.6V when the car hits 50MPH. Could it be that all I need to do is follow where the the other wire (blue) from the transmission goes and short the white to the blue wire thus bypassing the A/T oil pressure switch?
 
#20 ·
A couple of thoughts....first, we are dealing with 3rd hand info, and don't even know what code has been thrown - it's assumed that it's p0740?? Is it?
Also, is the car new to your son? Has the CEL been on all the time? Has your son cleared the codes and confirmed that the TCC code has come back, showing that it's in real time and not just in memory? I may be reading the diagram wrong, but it appears that the unused light blue wire is providing a ground to the TCC solenoid circuit???
And yes....dump that Haynes/Chilton. If you search the forum, you'll see evidence of the misinformation in it that people have followed, to their detriment....;)
 
#21 ·
The code is P0740 and yes it is a current code that causes the Service Engine Soon light to go on. There are no other fault codes. I've just acquired an OBD2 scan dongle thingy that communicates with my iPhone and I can clear the codes and the P0740 returns again shortly after the codes are cleared. The P0740 code has been cleared a number of times only to return as soon as the ECU runs its diagnostics. The code reads "TCC circuit open".
 
#22 · (Edited)
did a quick google on your code and found some interesting reading... including links back to posts in this forum!

https://www.google.com/search?q=+P0740+suzuki&ie=utf-8&oe=utf-8

One of the items that it says can cause it is low or dirty fluid. Has this been checked... properly? It is NOT done like you check motor oil.

Warm to hot (but not overheating), running in park on level ground.
 
#24 ·
The connector on the transmission is at an odd and difficult angle to reach behind the catalytic converter. I can't get my fingers in there to pull the connector without the hazard of breaking the wires. The Cat has been gorilla welded to the down pipe so pulling the exhaust could prove difficult. However, the transmission pan is accessible and not at all a problem to remove.

Still haven't received any confirmation that the TCC solenoid is actually replaceable by removing the pan.

It could also be a defective pressure switch if there is one. I've read that some '96 3spd autos had the pressure switch discontinued atthe factory becuase of problems. One of the problems is the return policy for electrical parts and the fact that these are special order items. I suppose that I could buy a pan gasket, remove the pan, and see for myself how things are wired. If I can't do anything with the pan removed, I could just reinstall the pan and reused the fluid as long as I kept it clean -- sort of a recon procedure.

The two wires coming off of the transmission head up over the transmission and it looks like they stay as a wrapped pair up to the relays in front of the battery where they begin to get wrapped up with other wires for about ten inches before the white wire comes out of the harness to the TCC relay. I'll unwrap the harness and find out where the blue wire leads off to.

Just wondering what people do when they convert from automatic to a manual transmission. I know its done on occasion.
 
#25 ·
... Just wondering what people do when they convert from automatic to a manual transmission. I know its done on occasion.
Most swaps that I have heard of are pre-OBD2 (1995 and earlier)... few checks and no codes like this.

I am (slightly) interested in OBD2 auto to manual swaps.... maybe they also swap the ECU (96) or PCM (97/98).
 
#26 ·
#27 ·
I've ordered a pan gasket, filter, and solenoid -- $92 total. I got assurance that I can return the solenoid if it "doesn't fit". The plan is to pull the pan and then I can see how the circuit is designed. Both my Autozone and AdvanceAuto stores do not show or have a source for a pressure switch. If there is one, I'll just bypass it should it prove defective.
 
#31 ·
Whether or not it was figured out, YOU, still need to determine why YOUR Tracker has the issue, so you need to go through the diagnostic steps.

Do you have the three speed or the four speed automatic?

On both transmissions, the torque converter clutch is engaged by hydraulic fluid pressure controlled by a solenoid valve, the solenoid could be defective, the fluid passages could be blocked, the torque converter could be defective, the wiring could be damaged or the control electronics could be faulty.

Start by monitoring the control signal to the solenoid, if it goes to 12V and the clutch does not engage the problem is in the transmission (possibly the solenoid), if it never gets to 12V, it's external. The solenoid can be partially tested using an ohmmeter, I say partially because the test just checks for continuity of the coil, it doesn't verify operation.
 
#32 ·
Welcome to the forum. Aside from the good information that Fordem has posted above, it is ALWAYS better to start your own thread, indicate exactly what you are driving, what the issue is, and what tests, if any, you’ve done to try to diagnose the problem. While symptoms can be the same, causes are often very different.