Uplugged power steering connector?
#16
Lexus Test Driver
iTrader: (5)
Join Date: Jan 2008
Location: New York
Posts: 838
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://www.clublexus.com/forums/images/icons/icon1.gif)
I have a 5 spd and it does not have it.
I always thought the 5 speeds didnt have anything connected to the plug and some automatic models have the plug (this is just an observation, not a fact).
For those posting if they have a connector there or not please state your year/model/transmission so we can get somewhere with this and put this connector mystery to rest.
I always thought the 5 speeds didnt have anything connected to the plug and some automatic models have the plug (this is just an observation, not a fact).
For those posting if they have a connector there or not please state your year/model/transmission so we can get somewhere with this and put this connector mystery to rest.
sidebar - I read on Supramania, one individual cutting one of the wires causing the power assist at high speeds to be active even during low speeds..
#17
Lexus Champion
iTrader: (10)
![Default](https://www.clublexus.com/forums/images/icons/icon1.gif)
yes, it would have an effect on the power steering if you have a plug on your harness and its actually plugged in vs not. I thought i read somewhere it was to do with automatic models with trac or without trac having them, i cannot remember which one exactly (not helpfull i know).
I just remember concluding that 5 spds didnt have them so I moved on... I spent a good amount of time under there searching high and low for a unused connector, but my harness did not have one.
I just remember concluding that 5 spds didnt have them so I moved on... I spent a good amount of time under there searching high and low for a unused connector, but my harness did not have one.
#19
Lexus Test Driver
iTrader: (5)
Join Date: Jan 2008
Location: New York
Posts: 838
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://www.clublexus.com/forums/images/icons/icon1.gif)
I have a 5 spd and it does not have it.
I always thought the 5 speeds didnt have anything connected to the plug and some automatic models have the plug (this is just an observation, not a fact).
For those posting if they have a connector there or not please state your year/model/transmission so we can get somewhere with this and put this connector mystery to rest.
I always thought the 5 speeds didnt have anything connected to the plug and some automatic models have the plug (this is just an observation, not a fact).
For those posting if they have a connector there or not please state your year/model/transmission so we can get somewhere with this and put this connector mystery to rest.
yes, it would have an effect on the power steering if you have a plug on your harness and its actually plugged in vs not. I thought i read somewhere it was to do with automatic models with trac or without trac having them, i cannot remember which one exactly (not helpfull i know).
I just remember concluding that 5 spds didnt have them so I moved on... I spent a good amount of time under there searching high and low for a unused connector, but my harness did not have one.
I just remember concluding that 5 spds didnt have them so I moved on... I spent a good amount of time under there searching high and low for a unused connector, but my harness did not have one.
#21
Lexus Test Driver
iTrader: (6)
Join Date: Aug 2008
Location: Maryland
Posts: 822
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://www.clublexus.com/forums/images/icons/icon1.gif)
iv had both auto and manual cars
1992 sc300 - auto - nontrac - plug on rack, no plug on harness
1995 sc300 - manual -nontrac - plug on rack, no plug on harness
1995 sc400 - auto - nontrac - plug on rack, no plug on harness
1992 sc300 - auto - nontrac - plug on rack, no plug on harness
1995 sc300 - manual -nontrac - plug on rack, no plug on harness
1995 sc400 - auto - nontrac - plug on rack, no plug on harness
Last edited by bryan767; 10-24-11 at 09:23 AM.
#22
Lexus Champion
iTrader: (10)
![Default](https://www.clublexus.com/forums/images/icons/icon1.gif)
and you have the plug on your harness side? that would mean its not limited to trac models.
does that mean you have a plug on the harness side but you just leave it unplugged, or you don't have one at all?
there must be a logical explanation for why SC's randomly have it.
there must be a logical explanation for why SC's randomly have it.
#23
Lexus Test Driver
iTrader: (6)
Join Date: Aug 2008
Location: Maryland
Posts: 822
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://www.clublexus.com/forums/images/icons/icon1.gif)
edited for clarity^
honastly its probably because they only made 1 rack for the sc3/400's and it didnt matter if you had trac or not. however if you did it had an extra plug on the harness to alter steering in a lose of traction scenario. thats my guess
honastly its probably because they only made 1 rack for the sc3/400's and it didnt matter if you had trac or not. however if you did it had an extra plug on the harness to alter steering in a lose of traction scenario. thats my guess
#24
Pole Position
iTrader: (15)
![Default](https://www.clublexus.com/forums/images/icons/icon1.gif)
Hey all, after doing some research, the steering connector as pictured by original poster is the power steering pressure switch.
The power steering pressure switch feeds information about demand on the power steering system to the vehicle's computer. At low speed, such as during parking lot maneuvers, the engine produces little power. Instead of waiting for the engine speed to decrease from the increased demand on power steering, the vehicle computer can compensate immediately for the increased load demand to keep the engine running smoothly.
The PPS "Progressive Power Steering" solenoid is a valve that varies the flow of hydraulic fluid to a reaction chamber - a fluid force that actually resists the power assistance. If a lot of fluid is allowed to flow to the reaction chamber, the steering effort is higher. If little fluid flows to the reaction chamber, then the steering effort is lower.
Key point: more fluid flow into the reaction chamber equals a higher steering effort.
Controlling the amount of fluid flowing to the reaction chamber is a solenoid. The solenoid (I assume - I haven't cut one open) consists of a coil, a return spring and the valve. When no current is applied to the solenoid, it opens, allowing more fluid to flow to the reaction chamber and so the steering to become heavier.
The current to the solenoid is varied by means of pulse width modulation - the current is pulsed on and off quickly. If it is on for only half of the time (ie it has a duty cycle of 50 per cent) the coil will 'see' only half battery voltage, and so will not close fully. If the duty cycle is reduced to, say, 30 per cent, then the valve will open a little more.
Note that unlike an injector, the frequency of the pulsing is so quick that the valve doesn't open and shut to the individual pulses - instead the plunger hovers at mid-points.
The PPS is controlled by its own dedicated ECU - a little box. It's a relatively simple box, too, with just one input - road speed. As speed goes up, the duty cycle with which it feeds the solenoid goes down and so the valve opens further, increasing steering heaviness. Or, to put it the other way, as the road speed falls, the solenoid duty cycle increases, closing the valve and so lightening the steering.
Here is a picture of the PPS solenoid
![](https://www.clublexus.com/gallery/data/4646/11.JPG)
Reference:
http://autospeed.com/cms/title_Modif...8/article.html
and
http://www.ehow.com/info_8748803_pow...switch-do.html
The power steering pressure switch feeds information about demand on the power steering system to the vehicle's computer. At low speed, such as during parking lot maneuvers, the engine produces little power. Instead of waiting for the engine speed to decrease from the increased demand on power steering, the vehicle computer can compensate immediately for the increased load demand to keep the engine running smoothly.
The PPS "Progressive Power Steering" solenoid is a valve that varies the flow of hydraulic fluid to a reaction chamber - a fluid force that actually resists the power assistance. If a lot of fluid is allowed to flow to the reaction chamber, the steering effort is higher. If little fluid flows to the reaction chamber, then the steering effort is lower.
Key point: more fluid flow into the reaction chamber equals a higher steering effort.
Controlling the amount of fluid flowing to the reaction chamber is a solenoid. The solenoid (I assume - I haven't cut one open) consists of a coil, a return spring and the valve. When no current is applied to the solenoid, it opens, allowing more fluid to flow to the reaction chamber and so the steering to become heavier.
The current to the solenoid is varied by means of pulse width modulation - the current is pulsed on and off quickly. If it is on for only half of the time (ie it has a duty cycle of 50 per cent) the coil will 'see' only half battery voltage, and so will not close fully. If the duty cycle is reduced to, say, 30 per cent, then the valve will open a little more.
Note that unlike an injector, the frequency of the pulsing is so quick that the valve doesn't open and shut to the individual pulses - instead the plunger hovers at mid-points.
The PPS is controlled by its own dedicated ECU - a little box. It's a relatively simple box, too, with just one input - road speed. As speed goes up, the duty cycle with which it feeds the solenoid goes down and so the valve opens further, increasing steering heaviness. Or, to put it the other way, as the road speed falls, the solenoid duty cycle increases, closing the valve and so lightening the steering.
Here is a picture of the PPS solenoid
Reference:
http://autospeed.com/cms/title_Modif...8/article.html
and
http://www.ehow.com/info_8748803_pow...switch-do.html
#29
![Default](https://www.clublexus.com/forums/images/icons/icon1.gif)
Did you ever do anything with this connector? I have the same issue where I do not have a connector on the harness that goes to the connector on the steering gear/R&P. Should there be a connector on the harness? Did you end up adding one? If you did, was there a change in your steering? Did you end up having/finding the PPS ECU?
Thanks,
Bruce
Last edited by bbyatv; 04-15-20 at 06:11 AM. Reason: Added question
#30
Lexus Champion
iTrader: (10)
![Default](https://www.clublexus.com/forums/images/icons/icon1.gif)
No I never found the connector (wasn't there) and it was always unplugged. Car drove great... still sort of a mystery to this day.
I didn't try and find the ecu, I don't think the 95 5spd would have had it but I sold that car so I can't really check or anything now.
If you have a connector hanging off your harness then plug it in, otherwise just ignore it seems to be the consensus.
I didn't try and find the ecu, I don't think the 95 5spd would have had it but I sold that car so I can't really check or anything now.
If you have a connector hanging off your harness then plug it in, otherwise just ignore it seems to be the consensus.