1HDT A442F Shifting Problems (1 Viewer)

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Apr 2, 2019
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Good day all,

Sorry for the trouble, have been browsing this forum for the past month trying to look for an answer. Already followed most of the solution you guys posted here with no luck. I have also downloaded most of the FSM related to engine and transmission.
I have a 1996 Landcruiser VXR HDJ80-GNPEX with 1HDT diesel engine and a A442F electrical transmission.
Original problem was lost of hidraulic pressure in my transmission and I had it rebuilt a couple of months back.
The mechanic replaced the solenoids, oil pump, torque converter, and driveplate.
Now its running ok again, but shifting is still not right.
I need to rev it past 2200 rpm, release the throttle, and then it shifts, either from 1 -2, 2-3. and also 3-OD.
Downshifting is normal.
Did a diagnostic thru the ODB and found error 41. Replaced the TPS but still same shifting manner.
Opened the ECT and it looks ok, still virgin never been tinkered before, so pretty sure ECT is ok.
I'm at lost now. The only thing I have not check is the transmission wiring harness. But I think this is too much, due to the fact that before the overhaul, shifting was fine.
My mechanic is also stumped, he does not have electrical manpower to find out the trouble if it was electrical.
So would like to hear from you guys, whether you have this kind of problem before.
I do believe this might be a small problem, something skipped or amiss. But then again, I only had this rig for less than a year. I just dont have the experience yet (hence noob) :p;)

Thank you very much and appreciate any inputs!...
 
Joined
May 26, 2008
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Leduc County
Whatever caused your loss of hydraulic pressure was not completely fixed. The new oil pump is probably compensating and allowing it to work. May be the hydraulic pressure regulator on the valve body. Whatever it is it's affecting all the shifts so I would use shared systems as your starting point.

Unfortunately the A442 FSM does not provide a troubleshooting guide.
 

IanB

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Jan 23, 2010
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Check the adjustment of your kickdown cable where it attaches to the throttle linkage, your FSM will show the proper adjustment where the orange stopper is on the cable. It makes a big difference if it's out of adjustment.
 
Joined
May 21, 2018
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Guyana, South America
I have the same problem where it shifts up pretty well except sometimes I need to back off the accelerator a bit or release and tap it for it to drop into the gear. I'm also getting what sounds like a singing sound coming from near the shifter when I get up to around 80-90 KM/H after having driven for about 25mins so it seems to happen when the tranny gets up to temperature.
 
Joined
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Messages
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Jakarta, Indonesia
Check the adjustment of your kickdown cable where it attaches to the throttle linkage, your FSM will show the proper adjustment where the orange stopper is on the cable. It makes a big difference if it's out of adjustment.

Hi IanB, thx for the input.
Forgot to mention that I also replaced the kickdown cable. The new cable does not have a steel mark on the cable. Yes i have tried to adjust it but so far shifting process is good, no bumps and smooth shifting. It just does this after 2200rpm + throttle release. Not really sure that the kickdown cable adjustment will decrease shifting rpm to say 1500.
 
Joined
Apr 2, 2019
Messages
6
Location
Jakarta, Indonesia
Whatever caused your loss of hydraulic pressure was not completely fixed. The new oil pump is probably compensating and allowing it to work. May be the hydraulic pressure regulator on the valve body. Whatever it is it's affecting all the shifts so I would use shared systems as your starting point.

Unfortunately the A442 FSM does not provide a troubleshooting guide.

Hi Mudzlla
Yes I am planning to borrow my friends bodyvalve and do a test.
Now its electronics is being checked so have to wait for results first.
Will post after done.
Thx for the input..
 
Joined
Apr 2, 2019
Messages
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Jakarta, Indonesia
I have the same problem where it shifts up pretty well except sometimes I need to back off the accelerator a bit or release and tap it for it to drop into the gear. I'm also getting what sounds like a singing sound coming from near the shifter when I get up to around 80-90 KM/H after having driven for about 25mins so it seems to happen when the tranny gets up to temperature.
CappiD,
Have you checked your transmission solenoids?
 
Last edited:
Joined
Jan 10, 2017
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Location
New England, USA
I have the same problem where it shifts up pretty well except sometimes I need to back off the accelerator a bit or release and tap it for it to drop into the gear. I'm also getting what sounds like a singing sound coming from near the shifter when I get up to around 80-90 KM/H after having driven for about 25mins so it seems to happen when the tranny gets up to temperature.

Probably dumb to mention.... Have you checked to make sure that the trans is full of fluid? I'm not sure on the electronic A442F but the procedure for some transmissions is to check with the vehicle in gear to ensure the fluid is cycling. I'm wondering if you have low pressure and the whining is related to either some air in the trans or even a gear type whine...
 

IanB

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Joined
Jan 23, 2010
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Winnipeg, MB
Probably dumb to mention.... Have you checked to make sure that the trans is full of fluid? I'm not sure on the electronic A442F but the procedure for some transmissions is to check with the vehicle in gear to ensure the fluid is cycling. I'm wondering if you have low pressure and the whining is related to either some air in the trans or even a gear type whine...

I believe the procedure is to slowly cycle through the gears and then check the fluid in P or N on these transmissions.
 
Joined
May 21, 2018
Messages
46
Location
Guyana, South America
Probably dumb to mention.... Have you checked to make sure that the trans is full of fluid? I'm not sure on the electronic A442F but the procedure for some transmissions is to check with the vehicle in gear to ensure the fluid is cycling. I'm wondering if you have low pressure and the whining is related to either some air in the trans or even a gear type whine...

I recently changed the fluid, and we did cycle through the gears, then checked the level. how do I tell if its a low pressure issue
 
Joined
Apr 2, 2019
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Jakarta, Indonesia
How do I check the solenoids?
Well, in order for you to observe the solenoids, you have to drop the transmission oil pan beneath the transmission box. You have to drain your transmission oil first so think about it before you do.
Bad solenoids would look blackish or burned, but it doesnt mean it does not work. It may still work but maybe not performing as standard. New solenoids might cost you $75 ish.
Before that, you might want to check also the kickdown cable adjustment. This is easier to do.
 
Joined
Jun 3, 2006
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Panama city, Rep of Panama
Solenoids can be checked by giving 12v to the harnes, it should be by the steering wheel...now...I had somewhat the same thing...it came to be very simple fix...on top of the diesel fuel pump is your TPS, follow the cable that comes from it and make sure it is attached to the cable that comes from the transmission harness...the pic below is the way to check solenoids...

SolenoidCHK.jpg
 
Joined
Apr 2, 2019
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Jakarta, Indonesia
Updates on my problems, after being checked by an electrical technician, he found that 2 bad transfer switch and 1 bad temperatur switch.
1960677


I wonder this could be the cause of my late shifting problem? But they do look bad, probably previous owner tried to fix it manually instead of changing the switches.
Will try to find spares and replace them and see how it goes.
 

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