Varaible Assist Steering, How does it work?

[Zack]

Reason I ask is because it just broke on Busters Old Car.
Is it controlled by that motor looking thingy on the rack and pinion?
Any suggestions welcomed.
Thanks

[magindat]

Zack,
I think electronics use the speed sensor input to adjust valving via solenoids in the rack.
That's the concept. I'm searching for more info.
Rich

[magindat]

Try this, dude...
http://www.aa1car.com/library/2004/bf10434.htm

[KillJoy]

WTH happened now?!?!?!?

KillJoy

[DeadVic]

as a slight aside to this question, does the same sensor control the "Speed Volume" on the head unit? I ask because on my 2001 CV the has very sensitive steering at speed and the speed volume doesn't work. I suspect it's either unhooked on not working.

Thanks

[Zack]

Now i need to determine if our car has the optical sensor in the column or not.

[RoyLPita]

Just so you know.......The module for the speed sensitive power steering also controls the rear air suspension.

[magindat]

as a slight aside to this question, does the same sensor control the "Speed Volume" on the head unit? I ask because on my 2001 CV the has very sensitive steering at speed and the speed volume doesn't work. I suspect it's either unhooked on not working.

Thanks

Both would be controlled by the speed sensor which I think is #18 (or #14) in the radio wiring harness. To check, put a voltmeter on it for positive and neg on VM to ground and drive. Voltage should vary with speed.

Gray/black #14 on radio harness (if the same as Marauder)

[magindat]

Now i need to determine if our car has the optical sensor in the column or not.

If you mean for the sudden turn at speed sensing function, look for a sensor pick up with wires on the rack away from the 'motor thingy'.

[magindat]

as a slight aside to this question, does the same sensor control the "Speed Volume" on the head unit? I ask because on my 2001 CV the has very sensitive steering at speed and the speed volume doesn't work. I suspect it's either unhooked on not working.

Thanks

Also, read the article linked above. The variable assist does not affect steering sensitivity, just provides more hydraulic assist at low speed and less as speed increases. I'm not sure if I could translate that into 'sensitivity' in my mind.

[Zack]

My steering problem is only at park or low speeds, just to clarify.
I remember that motor on the rack being able to rotate on my other two cars.
This one is fixed in place.

[magindat]

My steering problem is only at park or low speeds, just to clarify.
I remember that motor on the rack being able to rotate on my other two cars.
This one is fixed in place.

It is described as a stepper motor. It should move according to a variable amperage signal. Have you checked the signal? Or is the motor froze?

I'm assuming you mean it's not assisting at low speed.

[Zack]

Yeah, where do I get that signal from.
i can test it, just gotta know where to look. ????

[magindat]

Yeah, where do I get that signal from.
i can test it, just gotta know where to look. ????

Never looked at it, so bear with...
Is there not a plug on the stepper motor. Just wondering if there is signal going to the stepper.

It would work like a guage where an increasing/decreasing signal moves it's position and keeps it there. It doesn't spin like a motor. It moves more like a servo.

I would imagine the greatest signal (most opening) would be at idle/park therefore making the orifice largest for most assist.

[magindat]

I been watchin this thread to try and help out, but I gotta leave work. Zack, you'll have a PM shortly with my # if I can help.
Rich

[Zack]

Thanks for the help Rich.
Ill put a tester on the connector tonight or tomorrow and get the scoop.

[KilledKenny]

Here is some info for ya.The Variable Assist Power Steering (VAPS) system controls the level of power assistance available to the driver based on vehicle speed. Below 3.2 km/h (2 mph), full power steering assist is provided to lessen steering efforts and increase maneuverability. Between 3.2 km/h (2 mph) and 191 km/h (119 mph), steering assist will decrease gradually at a calibrated rate to raise steering efforts for increased directional stability and greater road feel. Above 191 km/h (119 mph), steering assist is constant.

The VAPS module outputs a pulse-width-modulated (PWM) current to the control valve actuator. The control valve actuator controls the hydraulic valve that determines the amount of hydraulic assist provided to the steering gear. The amount of assistance provided varies with the control valve actuator current, which is based on vehicle speed.

The vehicle speed is provided to the VAPS module by the powertrain control module (PCM)
The resistance of the vaps solenoid on the rack is approximately 6.4 ohms. The solenoid housing sometimes turns on the rack and sometimes it seizes to the rack, it does not effect operation when its seized to the rack. Here is a wirring diag for ya.

[Zack]

Awesome diagram, thanks KK.
now where is the VAPS module located?
Might be a loose/broken wire.
Ill start simple.

[KilledKenny]

Its located in right kick panal/glove box area.

[Zack]

fixed it!

A wire was pinched and eventually broke when i put everything back together.
It was broken between the oil filter housing and the PS pump.
Thanks for all the help.

[RCSignals]

fixed it!

A wire was pinched and eventually broke when i put everything back together.
.............


well, don't do that

[vegasmarauder]

That's pretty interesting Zack. When I bought my MM brand new, I thought the PS was a bit too sensitive at speed. When I stared looking at it, I saw that the factory had pinched the wire between the PS pump mount and the block when it was assembled. It had 12 miles on it. I took it in for a warranty repair. It's a tight fit...I point this out because if mine was built like that (300B, build 12/12/02) then they may still be others out there who don't realize their steering is not as tight as it could be.

Glad you fixed it easily tho....

[Zack]

That's pretty interesting Zack. When I bought my MM brand new, I thought the PS was a bit too sensitive at speed. When I stared looking at it, I saw that the factory had pinched the wire between the PS pump mount and the block when it was assembled. It had 12 miles on it. I took it in for a warranty repair. It's a tight fit...I point this out because if mine was built like that (300B, build 12/12/02) then they may still be others out there who don't realize their steering is not as tight as it could be.

Glad you fixed it easily tho....

Whats funny is this is the only Marauder Ive worked on that I routed these wires in the same factory location.
My other 2 cars I always re-route the wires because its such a tight fit in there.

[magindat]

Glad you're fixed.

[fastblackmerc]

So this may be my problem.... almost no assist when decelerating and turning at times.... Looks like warranty time....

[bugsys03]

http://www.300cforums.com/forums/srt8-general-discussion/29599-performance-9-land-steering-gear-does-my-srt8-have.html#post353202

Here is what the car SHOULD have from the factory

[Blackmoneyhole]

So this may be my problem.... almost no assist when decelerating and turning at times.... Looks like warranty time....

I have the same problem... I suspect a stuck valve on the rack. According to my LM dealer, you have to buy the whole rack, just to get the valve. List price on the rack was about $350. I think his price was about $169 (I took a peak on his screen). He said these are probably "factory remans"
In trouble shooting this system, If you unplug the valve on the rack, the valve should go to the full power state and your steering should be loose at highway speed. If this doesn't happen, then the valve is bad/stuck or something else is wrong with the rack.

What the heck... just turned 50,000 miles, Steering going, axles wearing out, rear tires won't last... Good thing I bought this car because I wanted something reliable...:bs:

[sailsmen]

Here is what the car SHOULD have from the factory[/QUOTE]

I like the SRT8. I was admiring a Charger last nite.

Everytime I go the car auction the Chrysler RWD are being pushed. A friend who goes once a month pointed it out to me.

They are usually the only cars being pushed. I don't understand.:confused:

[computertech]

Hey Guys
I just picked up a second 03 MM in Black on Black, I have what feels like no power steering @ any speed. Also when I start it up I can hear the air ride pump running, but the ride does`nt change.....

My other MM levels right out when I start it and the pump shuts down as well as baby smooth power steering

I have been reading this thread and it looks like i`ll be doing some searching in/around and under my dash tomorrow looking for the wire(s) that may be cut or pinched ????????

The car has a major aftermarket stereo, maybe it got cut while being installed ????

Anyone know wire color i`m looking for ? Location ?

all your help is greatly appreciated ! Thanks Guys for this great forum

[RoyLPita]

Hey Guys
I just picked up a second 03 MM, I have what feels like no power steering @ any speed. Also when I start it up I can hear the air ride pump running, but the ride does`nt change.....

My other MM levels right out when I start it and the pump shuts down as well as baby smooth power steering

I have been reading this thread and it looks like i`ll be doing some searching in/around and under my dash tomorrow looking for the wire(s) that may be cut or pinched ????????

The car has a major aftermarket stereo, maybe it got cut while being installed ????

Anyone know wire color i`m looking for ? Location ?

all your help is greatly appreciated ! Thanks Guys for this great forum

See post #7 in this thread.

[cyclopsram]

There is a wire which corrodes above the fender liner on the CVPI and limits the assist to about zero ..if you wiggle the fender liner, green crud falling is a good indicator...from the VTSP garage. Less power assist at speed, limits sensitivity of steering giving more road feel. More assist at slow speeds makes for easier turning of the steering wheel...

[KillJoy]

Dear Noobs,

Please start a new Thread about issues you are having, rather than bringing a long dead Thread back to life just to say you have the same problem.

First - Search. If you do not see an answer to you problem, START A NEW THREAD.

:rolleyes:

KillJoy

[MM03MOK]

Dear Noobs,

Please start a new Thread about issues you are having, rather than bringing a long dead Thread back to life just to say you have the same problem.

First - Search. If you do not see an answer to you problem, START A NEW THREAD.

:rolleyes:

KillJoy
:loco: Don't listen to him..... :rolleyes:

[marauder410]

I have this problem going to check into it