lokets
03-05-2006, 06:56 PM
Recently due to a recent scare driving jerkiness on my CVT Jazz, I was forced to reset the ECU/PCM and disconnect the battery to determine if this was the reason for the problem. In the end, it turned out to be a bad EGR.
Anyway, the exercise of reset of ECU/PCM or lost of battery power on a CVT Jazz requires recalibration of CVT. This is explained in the rather lengthy service manual. I followed through the procedure and could not find the same results as explained in the manual, and I wonder if anyone else had tried this and got similar result.
Let me select portions of the manual and highlight what I meant:
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There are 2 ways to reset calibrate the start clutch - one during halt (car not move) and another driving. I tried both but there's no way from the driving method to tell you if it worked or not (or perhaps the very act of driving actually calibrate it obviously). I prefer the static method which is supposed to give you feedback from the instruments that it is now OK.
According to the instruction you need a DLC pin box, a tool full of metal pins that has a data cable that connects to the data link connector (DLC), the "D" shape connector beneath your steering wheel, just beneath the air-con controls. This pin box allows you to easily short pins 4 & 9.
Pin 9 is the SCS (a signal to the computer that you are doing some "service") and pin 4 is the ground.
If you look at the "D" connector of DLC, the top-left pin is 1, next to its right is 2, etc. until the top-right corner is pin 8. Then, bottom left starts with pin 9, next to its right is pin 10, until bottom-right corner is pin 16. If you measure with a voltmeter, pin 4 is shorted to the car chassis (ie. ground). Pin 16 is battery power (12V).
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With this in mind, the procedure to recalibrate CVT is... bits & pieces from the book...
1. Apply the parking brake, and block all four wheels securely.
2. Warm up the engine to normal operating temperature (the radiator fan comes on).
3. Make sure that the MIL does not come on and the [D] indicator does not blink.
4. If the MIL comes on or [D] indicator blinks, check the fuel and emissions system or the A/T control system, and recheck after checking.
5. Turn the ignition switch OFF.
6. Connect the special tool (07WAJ-0010100) to the data link connector, then connect the jumper wire between terminals 4 and 9 at the special tool, and turn the switch ON to short-circuit SCS to ground.
** STEP 6: now if you don't have this "special tool" (aka the DLC pin box), you can connect a short wire between pins 4 & 9 - otherwise the following procedure is meaningless and system will not calibrate - unlike some other instruction elsewhere on other forums that omit this vital step.
7. Press the brake pedal, and continue pressing the pedal unit complete of the calibration.
8. Start the engine under no-load conditions, then turn the headlights on. The headlights must be turned on during calibration.
9. Shift the shift lever into [N] position, and shift to [D], [S], [L] position, then shift back to [S], [D], and into [N] in 20 seconds after the engine is started. The shift lever should stop at each position. Repeat this shifting twice.
10. Check that the [D] indicator comes on for one minute with the shift lever is in [N] position, then the indicator goes off.
11. If the [D] indicator blinks not to come on, or the [D] indicator comes on, and stays on (it does not go off after one minute). Turn the ignition switch OFF, restart the procedures with step 6.
12. Shift to [D] position, and check that the [D] indicator comes on for 2 minutes, then it goes off.
13. If the [D] indicator blinks not to come on, or the [D] indicator comes on, and stays on (it does not go off after one minute). Turn the ignition switch OFF, restart the procedures with step 6.
14. Turn the ignition switch OFF to reach completion.
15. Test-drive the vehicle to verify that a problem does not occur on the start clutch control system.
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OK, my "problem" is this:
After step 8, my [D] light does not come on - which is cool, as I think this is what you expect, as the system is in calibration mode.
I go through step 9, so far so good. But when it comes to step 10 - my [D] light does NOT come on for 1 min, when shifter is in [N]. And even if I repeat the procedure again from step 1, the same thing.
Also, I cannot get the same result from step 12 (step 10 & 12 should be inter-related, if you can't get one then forget the other I guess). I am uncertain why this happens.
Nevertheless, after I've done step 9 & repeated the cycle up to that point a couple of times, I stopped. My CVT presumably is calibrated - just that I cannot verify as I cannot get to step 10 & 12.
My questions are (open for discussion):
1. Have you tried this recalibration of CVT yourself? Or perhaps you can try it if you accidentally disconnect battery, some time in the future.
2. And if so, can you get the results as described in step 10 & 12, ie. [D] light is supposed to come on for some time.
--------
According to the book, you're supposed to do this recalibration when:
- Disconnecting the battery terminal(s)
- Removing the No. 20 ECU (15A) fuse in the under-dash fuse/relay box
- Replaced the start clutch
- Replaced the control valve body
- Overhauled the transmission assembly
- Replaced the transmission assembly
- Overhauled the engine assembly
- Replaced the engine assembly
I've been through the first 2 reasons (the other reasons are scary ones) & hence I went through the entire procedure but the result is not quite what I expect.
Thanks in advanced for any feedback or thoughts on this. :)
Anyway, the exercise of reset of ECU/PCM or lost of battery power on a CVT Jazz requires recalibration of CVT. This is explained in the rather lengthy service manual. I followed through the procedure and could not find the same results as explained in the manual, and I wonder if anyone else had tried this and got similar result.
Let me select portions of the manual and highlight what I meant:
--------
There are 2 ways to reset calibrate the start clutch - one during halt (car not move) and another driving. I tried both but there's no way from the driving method to tell you if it worked or not (or perhaps the very act of driving actually calibrate it obviously). I prefer the static method which is supposed to give you feedback from the instruments that it is now OK.
According to the instruction you need a DLC pin box, a tool full of metal pins that has a data cable that connects to the data link connector (DLC), the "D" shape connector beneath your steering wheel, just beneath the air-con controls. This pin box allows you to easily short pins 4 & 9.
Pin 9 is the SCS (a signal to the computer that you are doing some "service") and pin 4 is the ground.
If you look at the "D" connector of DLC, the top-left pin is 1, next to its right is 2, etc. until the top-right corner is pin 8. Then, bottom left starts with pin 9, next to its right is pin 10, until bottom-right corner is pin 16. If you measure with a voltmeter, pin 4 is shorted to the car chassis (ie. ground). Pin 16 is battery power (12V).
--------
With this in mind, the procedure to recalibrate CVT is... bits & pieces from the book...
1. Apply the parking brake, and block all four wheels securely.
2. Warm up the engine to normal operating temperature (the radiator fan comes on).
3. Make sure that the MIL does not come on and the [D] indicator does not blink.
4. If the MIL comes on or [D] indicator blinks, check the fuel and emissions system or the A/T control system, and recheck after checking.
5. Turn the ignition switch OFF.
6. Connect the special tool (07WAJ-0010100) to the data link connector, then connect the jumper wire between terminals 4 and 9 at the special tool, and turn the switch ON to short-circuit SCS to ground.
** STEP 6: now if you don't have this "special tool" (aka the DLC pin box), you can connect a short wire between pins 4 & 9 - otherwise the following procedure is meaningless and system will not calibrate - unlike some other instruction elsewhere on other forums that omit this vital step.
7. Press the brake pedal, and continue pressing the pedal unit complete of the calibration.
8. Start the engine under no-load conditions, then turn the headlights on. The headlights must be turned on during calibration.
9. Shift the shift lever into [N] position, and shift to [D], [S], [L] position, then shift back to [S], [D], and into [N] in 20 seconds after the engine is started. The shift lever should stop at each position. Repeat this shifting twice.
10. Check that the [D] indicator comes on for one minute with the shift lever is in [N] position, then the indicator goes off.
11. If the [D] indicator blinks not to come on, or the [D] indicator comes on, and stays on (it does not go off after one minute). Turn the ignition switch OFF, restart the procedures with step 6.
12. Shift to [D] position, and check that the [D] indicator comes on for 2 minutes, then it goes off.
13. If the [D] indicator blinks not to come on, or the [D] indicator comes on, and stays on (it does not go off after one minute). Turn the ignition switch OFF, restart the procedures with step 6.
14. Turn the ignition switch OFF to reach completion.
15. Test-drive the vehicle to verify that a problem does not occur on the start clutch control system.
--------
OK, my "problem" is this:
After step 8, my [D] light does not come on - which is cool, as I think this is what you expect, as the system is in calibration mode.
I go through step 9, so far so good. But when it comes to step 10 - my [D] light does NOT come on for 1 min, when shifter is in [N]. And even if I repeat the procedure again from step 1, the same thing.
Also, I cannot get the same result from step 12 (step 10 & 12 should be inter-related, if you can't get one then forget the other I guess). I am uncertain why this happens.
Nevertheless, after I've done step 9 & repeated the cycle up to that point a couple of times, I stopped. My CVT presumably is calibrated - just that I cannot verify as I cannot get to step 10 & 12.
My questions are (open for discussion):
1. Have you tried this recalibration of CVT yourself? Or perhaps you can try it if you accidentally disconnect battery, some time in the future.
2. And if so, can you get the results as described in step 10 & 12, ie. [D] light is supposed to come on for some time.
--------
According to the book, you're supposed to do this recalibration when:
- Disconnecting the battery terminal(s)
- Removing the No. 20 ECU (15A) fuse in the under-dash fuse/relay box
- Replaced the start clutch
- Replaced the control valve body
- Overhauled the transmission assembly
- Replaced the transmission assembly
- Overhauled the engine assembly
- Replaced the engine assembly
I've been through the first 2 reasons (the other reasons are scary ones) & hence I went through the entire procedure but the result is not quite what I expect.
Thanks in advanced for any feedback or thoughts on this. :)