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  #1  
Old 06-19-2008, 08:54 PM
hawaii-svx hawaii-svx is offline
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Please help-TCU code 22

My power light started blinking, so I pulled its codes I came up with "code 22 Atmospheric sensor" Can anyone please tell me? what this relates to? I have looked on the forums for about two hours now and cant find one thing about it. Any help would be very welcome.

Thanks,
Paul
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  #2  
Old 06-19-2008, 11:22 PM
oab_au oab_au is offline
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Re: Please help-TCU code 22

Quote:
Originally Posted by hawaii-svx View Post
My power light started blinking, so I pulled its codes I came up with "code 22 Atmospheric sensor" Can anyone please tell me? what this relates to? I have looked on the forums for about two hours now and cant find one thing about it. Any help would be very welcome.

Thanks,
Paul
I think Phil spoke about this code on his TCU thread. I have no info on a code 22. I don't think it is in all model TCUs.

Harvey.
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  #3  
Old 06-20-2008, 01:10 AM
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Re: Please help-TCU code 22

Quote:
Originally Posted by hawaii-svx View Post
My power light started blinking, so I pulled its codes I came up with "code 22 Atmospheric sensor" Can anyone please tell me? what this relates to? I have looked on the forums for about two hours now and cant find one thing about it. Any help would be very welcome.

Thanks,
Paul
Paul, nice to be able to address a member by name.

An atmospheric sensor is fitted to some models sold where pollution controls are strict and or, extremes in anticipated operating altitude levels apply. The sensor detects atmospheric pressure and sends a signal to the ECU.

If faulty the sensor could be affecting fuel consuption, but there is unlikely to be any immediate problem.

Phil may be able to add something, as he has run acroos the sensor in his investigations covering the ECU and TCU software.

Cheers, Trevor.
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Old 06-20-2008, 10:33 AM
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b3lha b3lha is offline
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Re: Please help-TCU code 22

The Atmospheric pressure sensor is fitted to US models. It is located inside the ECU, but is used by both the ECU and the TCU. A wire transfers the signal as a voltage level from the ECU to the TCU.

I think the ECU uses it as part of the EGR emissions control system and the TCU uses it as part of the line pressure control.

It is surprising that you are only getting the error code from your TCU. If the sensor was faulty then I would expect the ECU to give a code also. If you are lucky, it could be a problem with the wire between the ECU and TCU, but I don't know how such a problem could be caused until somebody has disturbed the wires. Are the plugs fitted clean and tight?

In any case, the problem must be inside your ECU, TCU or the wire between them. If you have access to a select monitor or PC adapter then you could check the atmospheric sensor reading at the ECU and TCU and compare them. But otherwise you are just going to have to try swapping parts out for known good ones.
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  #5  
Old 06-20-2008, 01:51 PM
hawaii-svx hawaii-svx is offline
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Re: Please help-TCU code 22

Thanks for the speedy reply Phil and Trevor.

I recently replaced the valve covers gaskets, which required me to unbolt the motor mounts and jack the motor up by doing so I may have inadvertently stressed the wires harness I will go back and check the harness and sensor fittings to see if something has become dislodged.

I will include an update if this works.

Thanks again,
Paul

harness.GIF
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  #6  
Old 06-20-2008, 04:40 PM
hawaii-svx hawaii-svx is offline
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Re: Please help-TCU code 22

(Sigh)

I went and disconnected and reconnected all of the relevant connections from the TCU and ECU and successfully stopped "code 22 Atmospheric sensor". I then got "code 25 Engine torque control signal". After a 1/2 hour of more unplugging, it has gone away as well. Unfortunately this has not remedied the original symptom that had me pulling codes.

When I leave my house the transmission will shift normally. After the first or second time of coming to a complete stop, the transmission will engage but the engine will only rev up to 2800rpm regardless if I am at 15% throttle or 100%. It will also stay in the same gear all the way up to 80mph when I run out of road, never shifting up or down. It will even do this if it's in manual mode and the shifter is in first gear.

The funny thing is if i get all green lights and don't come to a complete stop it will drive normal. I have tested this driving as far as 20 miles (the longest distance you can drive on Oahu without ever stopping). When I do stop I can, pull over, restart the car and it will start the process all over again.

One other thing I should mention is that I have no Existing codes but I do have a stored "code 12 Duty solenoid B" in my previous TCU codes. I have also pulled and checked the TPS and the resistor behind the battery and both are working and well withing operational range, (thanks for the how to write-ups on those bye the way). My miles per gallon went from 22 to about 13 after I started having this problem.

I greatly appreciate all the help I have received so far and would graciously accept any more help that is available.

Thanks,
Paul

Last edited by hawaii-svx; 06-20-2008 at 08:42 PM.
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  #7  
Old 06-20-2008, 11:41 PM
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Re: Please help-TCU code 22

[QUOTE=hawaii-svx;553078](Sigh)

Quote:
I went and disconnected and reconnected all of the relevant connections from the TCU and ECU and successfully stopped "code 22 Atmospheric sensor". I then got "code 25 Engine torque control signal". After a 1/2 hour of more unplugging, it has gone away as well. Unfortunately this has not remedied the original symptom that had me pulling codes.
This would give a clue that a plug/socket connection is possibly intermittent.

Quote:
When I leave my house the transmission will shift normally. After the first or second time of coming to a complete stop, the transmission will engage but the engine will only rev up to 2800rpm regardless if I am at 15% throttle or 100%. It will also stay in the same gear all the way up to 80mph when I run out of road, never shifting up or down. It will even do this if it's in manual mode and the shifter is in first gear.

The funny thing is if i get all green lights and don't come to a complete stop it will drive normal. I have tested this driving as far as 20 miles (the longest distance you can drive on Oahu without ever stopping). When I do stop I can, pull over, restart the car and it will start the process all over again.
This could indicate that the ECU not getting a signal from the TCU relative to
road speed. Have you tried the TCU for codes?
Whatever, you have a nasty problem in that all appears to be intermittent.

Quote:
One other thing I should mention is that I have no Existing codes but I do have a stored "code 12 Duty solenoid B" in my previous TCU codes. I have also pulled and checked the TPS and the resistor behind the battery and both are working and well withing operational range, (thanks for the how to write-ups on those bye the way). My miles per gallon went from 22 to about 13 after I started having this problem.
Solenoid valve "B" controls the lock up of the torque convertor. Does your transmission lock up as normal?

Quote:
I greatly appreciate all the help I have received so far and would graciously accept any more help that is available.
Thanks,
Paul
I hope the above comments may assist.
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