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I recently had the 3 pressure sensors replaced in the transmission. The dodson package comes with a module that taps into the tcm in the trunk. Does anyone know what the button does on the module? Also, since the install I get sporadic transmission codes that put me in limp mode. I shut the car off, jiggle the wires and it usually fixes the problem when I start the car back up. All connections seem to be solid. Anyone have issues with this before and know a fix?
 

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Discussion Starter · #2 ·
Found out what the button does. With engine off but ignition switch to on holding down the button for 5 seconds resets/calibrates all sensors to 500mV which is the pressure reading they should be at with ambient pressure i.e. engine/trans not operating
 

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Goofball in a racecar
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It sets the trims, youj push it to make the sensors work. You can also handle the sensors in a tcm tune without the need to wire into the tcm

Sent from my SM-G892U using Tapatalk

 

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Has anyone here gone the "software route" and not installed the conditioning box for the Dodson Pressure Sensors? If so, I'm curious as to what your long term experience has been and if you had any issues performing a clutch calibration. I wrote to Dodson asking if simply re-scaling the sensor voltage offset in the TCM map was an OK alternative option to using the conditioning box and this was what they said.

Yes the scaling for the sensor can be changed in the TCM map, but then it loses resolution and it will fail the clutch calibration procedure because it cant detect the little fluctuations it does at the start of the procedure. Our scaling box that is wired in also has a reset button which automatically sets all sensors to 500mV, so even after a long period of time when the sensors start to fall away, you can reset them back to 500mV.

The TCM reads mV as opposed to the actual pressure value. When you run our 68 bar sensor as opposed to the factory 28 bar sensor, The mV reading changes by a factor of 2.4. Our scaling box changes the mV reading it sends to the TCM so the resolution with our box is identical to that of the OEM setup.

Just something I've noticed when trying to avoid wiring the box in the past.
 

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Has anyone here gone the "software route" and not installed the conditioning box for the Dodson Pressure Sensors? If so, I'm curious as to what your long term experience has been and if you had any issues performing a clutch calibration. I wrote to Dodson asking if simply re-scaling the sensor voltage offset in the TCM map was an OK alternative option to using the conditioning box and this was what they said.

Yes the scaling for the sensor can be changed in the TCM map, but then it loses resolution and it will fail the clutch calibration procedure because it cant detect the little fluctuations it does at the start of the procedure. Our scaling box that is wired in also has a reset button which automatically sets all sensors to 500mV, so even after a long period of time when the sensors start to fall away, you can reset them back to 500mV.

The TCM reads mV as opposed to the actual pressure value. When you run our 68 bar sensor as opposed to the factory 28 bar sensor, The mV reading changes by a factor of 2.4. Our scaling box changes the mV reading it sends to the TCM so the resolution with our box is identical to that of the OEM setup.

Just something I've noticed when trying to avoid wiring the box in the past.
This is actually very helpful info. After issues even with the latest oem sensors I'm going back to the Dodson ones and will use the conditioning box
 

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Just to follow up, I did NOT use the box. I simply rescaled the sensor voltages in my map and I have been running it this way for over a year now with zero issues. You need only adjust 5 tables. Clutch A Sensor 1 & 2, Clutch B Sensor 1 & 2, Line Pressure. Simply change the upper value for all 5 to 870.23 for the Dodson sensors.
 

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i had new dodson sensors and control box installed then two weeks later i got a pressure sensor A failure and a line sensor failure.

the problem seems to be intermittant, it comes and goes.

i had the dealership wire the box in and they re-wired as part of tracking down the issue

nissan says pressure sensor A is stuck at 485 mv and does not move off this number while sensor B fluctuates yet the car shifts fine

apparently the mv must fluctuate as the gears change (even slightly) so it cannot be stuck without kicking a code every time the car is started.

the guy who did the transmission work wants the car to diagnose it properly he feels the nissan dealership testing equipment may have been faulty.
 

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Just to follow up, I did NOT use the box. I simply rescaled the sensor voltages in my map and I have been running it this way for over a year now with zero issues. You need only adjust 5 tables. Clutch A Sensor 1 & 2, Clutch B Sensor 1 & 2, Line Pressure. Simply change the upper value for all 5 to 870.23 for the Dodson sensors.
No issues with doing a relearn?
 

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Nope.
 

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i had new dodson sensors and control box installed then two weeks later i got a pressure sensor A failure and a line sensor failure.

the problem seems to be intermittant, it comes and goes.

i had the dealership wire the box in and they re-wired as part of tracking down the issue

nissan says pressure sensor A is stuck at 485 mv and does not move off this number while sensor B fluctuates yet the car shifts fine

apparently the mv must fluctuate as the gears change (even slightly) so it cannot be stuck without kicking a code every time the car is started.

the guy who did the transmission work wants the car to diagnose it properly he feels the nissan dealership testing equipment may have been faulty.
@aarongtr did you resolve this issue?
 

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No in fact the replacement to the dodson sensor (another dodson sensor) is giving us some inline sensor misreadings or something according to my mechanic recently.

the car has been in Vancouver for close to 2 months at his shop as he can only deal with it as he has time and when he can get the problem to re-occur so he can

do more data logging. very frustrating issue especially due to the intermittant nature of it.
 

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I wonder if the transmission harness wires/plugs/pins could have been damaged in the re/re
 

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apparently a pirated line sensor from a 2017 trans seems to have fixed the issue. the mechanic saw line sensor readings he was not liking.

the wiring was re-done, twice by nissan and once by the mechanic who really knows the GTR he ruled out the wiring and the module.

apparently it was dodson part issues, a faulty sensor and then inconsistent line pressure readings until he put the used line sensor in the valve body.

car running fine now will update if it changes. thanks for all your input folks!
 

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apparently a pirated line sensor from a 2017 trans seems to have fixed the issue. the mechanic saw line sensor readings he was not liking.

the wiring was re-done, twice by nissan and once by the mechanic who really knows the GTR he ruled out the wiring and the module.

apparently it was dodson part issues, a faulty sensor and then inconsistent line pressure readings until he put the used line sensor in the valve body.

car running fine now will update if it changes. thanks for all your input folks!
I am having the same exact issue with a brand new Dodson Sensor...Gearbox was built by Shep and Installed by ACG, both which are top rated GTR shops...

Im wondering if Dodson is on a run of faulty sensors or have a Quality Control issue??
 

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Is it intermittant in wanting to go into limp mode?
It doesnt go into limp mode. ONLY After a cold start, when partial warm (~120degF) the sensor drops (0mV) and stays off. The loss of sensor causes the check engine light (traction light) but no functional issues. If I power cycle the car, the sensor works properly and the DTC goes away.

Apparently it is a faulty sensor which sucks but at least the gearbox doesnt need to be dropped. I was told bad sensors dont like temperature swings.

I had all new sensors and the control module installed. A reset of the module was performed and the external wiring was checked but it didnt change the issue.
 

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No in fact the replacement to the dodson sensor (another dodson sensor) is giving us some inline sensor misreadings or something according to my mechanic recently.

the car has been in Vancouver for close to 2 months at his shop as he can only deal with it as he has time and when he can get the problem to re-occur so he can

do more data logging. very frustrating issue especially due to the intermittant nature of it.
Which shop?
 

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I think I am experiencing this same issue. Just dropped the trans and replaced sensors with three new Dodson ones and now Im having this issue. Ill report back once the trans comes back out.
 
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