[4th Gen : 01-07]: Limp Mode -- Replacing Solenoid BUT is DRBIII Scan Tool REQUIRED ??
#1
10-29-2018, 10:26 PM
Limp Mode -- Replacing Solenoid BUT is DRBIII Scan Tool REQUIRED ??
Vehicle: 2002 Dodge Caravan SE (3.3, V6)
The vehicle was in limp mode and was told the Solenoid / Pressure Switch Assembly was leaking. At the moment the vehicle appears to be fine -- no more shift issue like before.
I dont want to take any chances. I have the service manual so will go about replacing the Solenoid / Pressure Switch Assembly. The manual goes on to say if the assembly was replaced to perform a TCM Quick Learn via a DRBIII Scan Tool. My understanding is this is an expensive tool which has nothing to do with a standard OBDII unit.
My question is can the vehicle automatically re-learn without using the DRBIII scan tool or is the relearn tool a must? This guy on YT (see video below) replaced the Caravan's Solenoid then states one should simply drive the car for 30 mins to have the vehicle re-learn. Is this true? There are no DTC error codes despite having experienced the failure in switching into (D) and the car not moving then having to jostle about 2nd and 3rd before the car moved on 3rd.
Thanks.
The vehicle was in limp mode and was told the Solenoid / Pressure Switch Assembly was leaking. At the moment the vehicle appears to be fine -- no more shift issue like before.
I dont want to take any chances. I have the service manual so will go about replacing the Solenoid / Pressure Switch Assembly. The manual goes on to say if the assembly was replaced to perform a TCM Quick Learn via a DRBIII Scan Tool. My understanding is this is an expensive tool which has nothing to do with a standard OBDII unit.
My question is can the vehicle automatically re-learn without using the DRBIII scan tool or is the relearn tool a must? This guy on YT (see video below) replaced the Caravan's Solenoid then states one should simply drive the car for 30 mins to have the vehicle re-learn. Is this true? There are no DTC error codes despite having experienced the failure in switching into (D) and the car not moving then having to jostle about 2nd and 3rd before the car moved on 3rd.
Thanks.
Last edited by quantass; 10-29-2018 at 11:10 PM.
#2
10-30-2018, 09:02 PM
Yes, the ECM/TCM will automatically relearn the shift values. I can't verify that 30 minutes of drive time is all that's required, but what you want to be doing is driving through the city or performing as much stopping and accelerating as possible. What the computer is trying to learn is the volume of fluid required to cause a clutch pack to engage from one shift to another. Be prepared that until these values are fully learned, transmission operation can feel quite harsh.
The point of having a scan tool (DRB III or otherwise) and performing a quick learn procedure is to get the computer to learn these values quicker. That way, if a shop performs the repair, they can do the quick learn to prevent a customer from immediately coming back with concerns that their van is shifting hard.
Make sure to disconnect the negative battery cable while replacing it, then take a minute before you actually drive it to shift into each gear (pausing for 2-3 seconds each) and feel for engagement. This will help set the initial values.
The point of having a scan tool (DRB III or otherwise) and performing a quick learn procedure is to get the computer to learn these values quicker. That way, if a shop performs the repair, they can do the quick learn to prevent a customer from immediately coming back with concerns that their van is shifting hard.
Make sure to disconnect the negative battery cable while replacing it, then take a minute before you actually drive it to shift into each gear (pausing for 2-3 seconds each) and feel for engagement. This will help set the initial values.
#3
10-30-2018, 11:18 PM
Thanks for the response.
Just because this is all new to me and i dont want to mess up, are you saying once i have the new pack installed and fluids topped up i should take the vehicle for a drive -- first start in (D) and drive keeping things under 50 KM/h or whatever to keep it on first gear but then manually shift the vehicle into (3) then (L) then bakc to (3) then to (D) ? Once this inital phase is over i should simply drive the vehicle as usual but expect the car to have a JERK motion when it automatically shifts? Of course this jerking will come to an end after XX kms.
Just because this is all new to me and i dont want to mess up, are you saying once i have the new pack installed and fluids topped up i should take the vehicle for a drive -- first start in (D) and drive keeping things under 50 KM/h or whatever to keep it on first gear but then manually shift the vehicle into (3) then (L) then bakc to (3) then to (D) ? Once this inital phase is over i should simply drive the vehicle as usual but expect the car to have a JERK motion when it automatically shifts? Of course this jerking will come to an end after XX kms.
Last edited by quantass; 10-30-2018 at 11:27 PM.
#4
10-31-2018, 09:49 PM
You don’t have to manually control the forward shifts. I only meant the gears available with the shifter lever (my van only shifts to reverse, neutral and drive, but if yours has manual gears then shift to those as well).
So, keeping your foot on the brake and not allowing the vehicle to move, shift through all the gears available on the shifter lever, pausing for 2-3 seconds in each position. This will help the computer learn initial values.
On the drive, expect abnormal operation at first. I can’t tell you exactly what it will do, because each vehicle is different. I’ve been on test drives after repairs that felt like the transmission was going to rip itself apart and test drives where it was noticeable but not terrible. For the most part, it should be shifting relatively smoothly after 10-15 minutes, but it could take a few days for it to feel completely normal again. The best thing you can do to speed up the process is drive from a complete stop to highway speed, then back to a complete stop and repeat.
The computer needs to learn the values for up shifting as well as down shifting, so manually controlling the shifts during the drive is not recommended.
So, keeping your foot on the brake and not allowing the vehicle to move, shift through all the gears available on the shifter lever, pausing for 2-3 seconds in each position. This will help the computer learn initial values.
On the drive, expect abnormal operation at first. I can’t tell you exactly what it will do, because each vehicle is different. I’ve been on test drives after repairs that felt like the transmission was going to rip itself apart and test drives where it was noticeable but not terrible. For the most part, it should be shifting relatively smoothly after 10-15 minutes, but it could take a few days for it to feel completely normal again. The best thing you can do to speed up the process is drive from a complete stop to highway speed, then back to a complete stop and repeat.
The computer needs to learn the values for up shifting as well as down shifting, so manually controlling the shifts during the drive is not recommended.