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  #1  
Old 05-15-2008, 11:03 PM
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what exactly does the trans resistor do?

i unplugged mine today and drove it for about a 1/2 mile. i was wondering what exactly it does. do you really need it? i guess what im looking for is just some general info about it and its function. thanks!
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Old 05-15-2008, 11:07 PM
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It directly effects solenoid A. Trevor can supply you with all the info on this as he knows it quite well. Do a search for it.
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Old 05-15-2008, 11:16 PM
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i did a general search about it but nothing really came up that "taught" me anything about it. i didnt go extremely deep, but i did read about soleniod A. also that the line pressure being at 100% can damage a valve? anyway, i just dont really understand what its ACTUALLY doing. also, i read somewhere that when the resistor is not connected the transmission acts alot different. i couldnt really tell a difference except for the fact that it shifted much quicker and slightly harder, but nothing violent. is that normal?
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Old 05-17-2008, 12:55 AM
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Seems to me.....

that there is not much reason to tamper with it. Harder shifting might not be too good on the transmission.
I have tried the small parts kit from Tacoma wa and ended up just putting the resister back in the circuit.

Your call!

Keith
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Old 05-17-2008, 06:15 AM
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i bought a new resistor on here when i first got my car from svxfiles and have had it in there ever since. yesterday i put in my old one, and i hardly noticed a difference in shifting. should i have noticed a large difference? and when i took the resistor out completely should i have noticed a larger difference?
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Old 05-17-2008, 06:53 AM
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The higher the resistance in the circuit for the Duty Sol. A the less the duty cycle is. Thus increasing line pressure in the transmission. The increased line pressure or lack of line pressure control creates firmer shift but also creates confusion in the gear box when the selector is in 3 and the car is slowing down as it will hunt for gears... More or less it is to firm up the shifts

Tom
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  #7  
Old 05-17-2008, 11:53 AM
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the majority of my driving time is spent in 3, does this "hunting" for gears damage anything?
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Old 05-22-2008, 10:27 PM
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Quote:
Originally Posted by JLHollowX13 View Post
the majority of my driving time is spent in 3, does this "hunting" for gears damage anything?
Set out below is a write up I prepared some time ago covering details including the resistor:-

THE DROPPING RESISTOR CIRCUIT.

It will be immediately apparent that the sudden on off pulse width modulated duty to which solenoid valve “A” is subject, tends to cause what could be called a hammering of the valve seat, even though this is largely reduced/damped by the controlled fluid flow.

The dropping resistor introduces a second series of current pulses applied in parallel with the control signal. These shorter pulses are applied during the off cycles and are timed to check the travel of the armature as it reaches the closed position, thus reducing both shock and noise. These secondary parallel signals in effect, “round off” the closing period and reduce the closing shock.

It will be appreciated that increasing the resistance in the circuit, or opening the circuit by omitting the dropping resistor, has two outcomes. Firstly the relative electrical off time is increased, thus increasing the line pressure and therefore makes shifts more abrupt. Importantly as an undesirable second issue, shock loads applied to the valve are increased.

It is a recognized fact that the line pressure control solenoid is the first to fail, due to having to fulfill by far the most arduous duty. Failure is usually mechanical resulting in the valve seat not closing properly and as a result line pressure is markedly reduced. The end results are drastic, especially in respect of transmission friction surfaces.

The resistor should measure between 9 and 15 ohms to be within specifications. The usual is about 12 ohms.


You are doing the absolutely correct thing by driving in third when in traffic etc. In fact this will reduce hunting between gears, as fourth/overdrive will not become involved immediately light transmission loading is available.
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Old 05-23-2008, 06:42 AM
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Quote:
Originally Posted by Trevor View Post
Set out below is a write up I prepared some time ago covering details including the resistor:-

THE DROPPING RESISTOR CIRCUIT.

It will be immediately apparent that the sudden on off pulse width modulated duty to which solenoid valve “A” is subject, tends to cause what could be called a hammering of the valve seat, even though this is largely reduced/damped by the controlled fluid flow.

The dropping resistor introduces a second series of current pulses applied in parallel with the control signal. These shorter pulses are applied during the off cycles and are timed to check the travel of the armature as it reaches the closed position, thus reducing both shock and noise. These secondary parallel signals in effect, “round off” the closing period and reduce the closing shock.

It will be appreciated that increasing the resistance in the circuit, or opening the circuit by omitting the dropping resistor, has two outcomes. Firstly the relative electrical off time is increased, thus increasing the line pressure and therefore makes shifts more abrupt. Importantly as an undesirable second issue, shock loads applied to the valve are increased.

It is a recognized fact that the line pressure control solenoid is the first to fail, due to having to fulfill by far the most arduous duty. Failure is usually mechanical resulting in the valve seat not closing properly and as a result line pressure is markedly reduced. The end results are drastic, especially in respect of transmission friction surfaces.

The resistor should measure between 9 and 15 ohms to be within specifications. The usual is about 12 ohms.


You are doing the absolutely correct thing by driving in third when in traffic etc. In fact this will reduce hunting between gears, as fourth/overdrive will not become involved immediately light transmission loading is available.
Glad to have ya back Trevor

Tom
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  #10  
Old 05-23-2008, 09:49 AM
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Yes!

Quote:
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Glad to have ya back Trevor

Tom
...................
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  #11  
Old 07-16-2008, 02:57 PM
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Re: what exactly does the trans resistor do?

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Originally Posted by TomsSVX View Post
Glad to have ya back Trevor

Tom
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  #12  
Old 07-22-2008, 12:21 AM
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Re: what exactly does the trans resistor do?

glad to see you back trevor
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  #13  
Old 07-22-2008, 03:52 AM
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Re: what exactly does the trans resistor do?

I don't think Trevor is back yet. You guys are replying to a post from before he got banned.
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  #14  
Old 07-22-2008, 06:57 AM
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Re: what exactly does the trans resistor do?

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glad to see you back trevor
yea that was after he had his stint in the hospital.

Tom
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  #15  
Old 07-22-2008, 12:58 PM
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Cool Re: what exactly does the trans resistor do?

Trevor - we all missed your inputs !!!!

Steve (1 OF 1)
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