P0740 code

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sorry for your grief !

Hi!

Failed NJ state emissions test with P0740 and an inoperative MIL.

I bought a salvaged instrument cluster that fixed the burnt out MIL plus took away my screeching speedometer. I took apart the original speedo with 132k miles and learned that even with the copper cup and needle removed I still had noise from the bushing for the magnet. New to me cluster seems all a go and has only 83k miles.

Back to P0740. Not knowing what a TCC is I have relied only on my 1997 Factory service manual. TCC is he front fluid clutch lock.

My vehicle: 1997 Tracker 2 door convertible 1.6 liter 16V automatic 4x4

Let me say I have NO driveability issues. All gears engage smoothly, though I am unsure in my ability to sense the application of the TCC around 50 mph. If I tap the brakes at 50+mph while holding steady throttle then my answer would be that the engine RPM do NOT blip up. Tcc IS DEAD.


I do not know for sure what I am doing and I may be 100% wrong. I get 25-26 mpg with mixed driving.

The automatic is a 3 speed 3L30 and there is a whole diagnostic section for code P0740. I have learned my way through the electrical diagnosis steps 1-9. Each value has been a YES, which directs me from step 9 to step 15. I only own a $15 code reader that does not give me values during a drive test, but while driving down a level road with steady throttle my Engine RPMs with my instrument cluster tachometer are real close to the specified values of 3000 rpm at 55 mph and 3500 rpm for 65 mph. With this the diagnostic tree points me to #16 which call for me to plug in a known good PCM. Hmphf! Santa did not put one in my stocking this year.

You could cut the ttc ,wire and hot wire it , driving, see if it works
------[/u]you mean once I get to 50 mph then I make the wire connection?
also is the ohms to ground correct, not infinity.
-------i am not sure. Here is what I tried per fsm: step 7 of diagnostics tree had me ohm the TCC relay terminal 4 to ground and I had 27 ohms at 40 degrees Fahrenheit (this step was described as testing the TCC solenoid for proper resistance, the book said perfect would be 30-36 ohms at 68 degrees Fahrenheit. Was I close enough as I was colder than spec? Maybe I am worse and the TCC has wrong resistance.)
if trans is older than 1996 , there was a tcc pressure switch there, delete it and jumper to solenoid works all the time.
-------[u]seems I can skip this step being a 1997


Do I trust the factory service manual for the diagnostics? Should I track down a salvage yard PCM?
do not buy a pcm, use a voltmeter on the 1 wire, if it goes to 12vdc at 50mph, the PCM is good!!!
-------Mmm, step 9 of fsm me jack up rear wheels, get motor running at full warm and put tranny in drive up to 47 mph--I just got between 50-55mph and measure voltage by back probing TCC relay pin 4 and ground and I had 14.5 volts which the fsm said was a passing grade for TCC solenoid operation.

How much is a PCM? $50 used pigs in pokes to or $400 from Cardone , do the tests. let me help
I was real happy that the instrument cluster was $90, but I could see on eBay that this was in line. I did not see many PCMs, plus how do I know which years work?
Just 1997 see my pcm pdf pages real suzuki page,
1997 suzuki moved the TCM in to the ECU, soin .... big deal that.


The cluster was easy to match up at the salvage yard counter, but I do not know how to shop for a PCM. I DO.
-------[/u]smiles

I sure need an inspection sticker and have until 2-28-15 to get this fixed.

Thanks for reading!

Allen

steps, did you pull the trans side connector (left) and ohm out the Tcc WIRE TO GROUND
-------no, I have either been at tcc relay or at pcm connector c1
IS THE tranny ground strap in place
-------do not know, but I will investigate
is the tcc wire going to 12vdc at 50,MPH
-------i think so per step 9 mentioned above

DO NOT BUY PARTS YET, WE CAN PROVE WHAT IS WRONG, EASY.
-------sounds great, plus I learn more

LONG Ago the fender Tcc RELAY was deleted.
then the TCM uses a high power transistor to drive the TCC LINE,
so only voltage matters from the TCm (Er, pcm) the line hits 12vdc that is IT , the PCM job ends. easy huh?
so i measure pin on side of trans, for my guess 30 ohms? its on my 3l30 page. but not infinity
-------i think mine was 27 ohms at 40 degrees...good?
infinity, or huge ohms like 100, that is bad.
pan off (sorry)?) pcm good, pan off
pan off , and i look a the tcc wire, is it broken, is it going to the silly pressure switch deleted in 1995? yes, get rid of it, the TSB warns of that.
pressure switch gone, bypassed, we then check ohms again, ah 30 ohms or 20 not high. good, no its infinity and bad new tcc solenoid right there. on wire end.

there if the solenoid ohms is good, hot wire it do you hear it open, yes, good, no bad
-----OK, I have NOT asked the solenoid to make noise. I will look at wire diagram to see what I jump. I am putting something straight to ground?
ok it makes noise,
we then bench test it per fsm page, i have ,,,,, using 12vdc and a air pressure or oil can with trigger, pressure feed it crudly
most shops just use shop air to test the valve, open yes, closed yeas, with no 12v. opens with 12vdc
easy huh
-------I have ordered dexron III a gasket and filter and will check for tips I have missed or forgotten. You cover a lot of ground!

beyond that, its bad lock time, not good news that.
-------fingers crossed!

-------Great learning and fun. Many thanks!!!




cheers=

ps, ask questions.