Un-power steering

[thomash85715]

Today I was trying to parallel park in tight spot in carport and went several lock-to-lock cycles with the steering. SHOCKED to find I had burned off three miles of range doing this. So how can we disable the overkill power steering? I looked in book for fuse identifying it but nothing. My idea was to pull that fuse. There is a thread on here starting with forward shields down which did contain some pictures of the steering components as seen from underneath but they are missing. Has anyone pulled the power cable off the PS pump to see how many more miles we might get? One person stated he thought the car was light enough to steer manually and I totally agree.

 

[wmcbrine]

Just because you lost 3 miles on the Range Remaining indicator, doesn't mean you actually lost any range. Get more accurate readings (from e.g. Canion) before you do anything drastic, at least.

 

[thomash85715]

I don't know anything about canion. Does it require a blutooth device plugged in to the OBD2 plug? How else could something know what the car was really doing? I have a spare one of those dongle things not being used.

 

[kiev]

yes, purchase an LX OBDlink dongle for $50 from scantool.net and download the android app, Canion, to monitor the voltage and current of the pack. It must be the real deal using the STN1110 chip, not a fake using ELM327, else it won't work.

 

[Don]

Something else is going on - I can sit in the parking lot with the A/C running for half an hour waiting on the wife to finish shopping and not burn off 3 miles of range. No way the power steering is using that much . . . . unless you spent an hour trying to get it parked :lol:

I'm not sure what the computer would do if you disabled the power steering by pulling a fuse - Likely the car would fault and go into safety mode and only allow you to drive it at 20 mph to the nearest repair facility. The computer controls everything in this car - ABS, ASC (Active Stability Control), TCL (Traction Control Logic) - If Mitsu intended the car to operate normally without power steering, they would have given you a switch to disable it

Don

 

[PV1]

While the Smart ForTwo has optional power steering (and if I were buying one, it wouldn't have it as that car is light enough to not need it), I feel that Mitsubishi did the proper thing by having power steering standard. It is just a tad to heavy to forgo it. Tight turning in a parking lot would suck without it.

I would say the 3 RR drop was a result of the total draw of the car systems, power steering, and the motor moving the car back and forth, and not solely because of the power steering.

 

[PV1]

I've been driving Koorz this week (for mental health more than anything. These cars just make me happy ), which is sadly now a 50-mile car (40 mile drive leaves 10 RR each night), and was thinking about this during this morning's drive. Has anyone ever put a number on the power draw of the power steering? What about a way to disable it? Likewise, I couldn't locate a fuse for it (perhaps it runs from high voltage or has a dedicated feed line from the 12 volt battery?).

 

[PV1]

Found some info in the service manual for the Power Steering. It’s rated at 12 volts, 30 amps for input at the EPS-ECU, so it is one of the big power wires coming from the 12 volt battery. It looks like there is an 8-pin connector that if unplugged, takes all power away from the power steering system. Theoretically, it should be able to be unplugged without setting off any error codes, but that depends on other ECUs not complaining from the EPS giving them the silent treatment.

However, if it pulls its rated power continuously (which we know it won’t), that is a consistent power draw of 360 watts, which for my 40-mile round-trip drive, works out to about 13.5 Wh/mile. Over a full charge, I might gain 2 miles of range by losing power steering. Realistically, maintaining tire pressure would net me a larger efficiency gain unless I drive all windy back roads.

 

[WReed82]

Hi Folks,

Many years ago I drove a two-ton1958 cab-over-engine Ford flatbed
delivery truck that didn't have power steering.
Driving this truck I learned that if you were moving even just slightly forward or backward,
steering was pretty easy. Most folks don't have a clue about how much tire rubber they are
scrubbing off with their power steering in a paved parking lot.

My current pickup truck is a 1982 Toyota with a heavy diesel engine that gets 44mpg; no power steering.
Occasionally I'm in tight spots where I have to turn the steering wheel lock-to-lock, it
does take some effort, but is very manageble even for an old guy.

The IMiEV is so light at the front that they put narrower tires there.
My guess is it only has power steering because some marketer said manual steering wouldn't sell.
If the steering were designed from the start to be manual, the car would be lighter, simpler,
have fewer points of failure and would go farther on a charge.
And it would still be fairly easy to steer.

I'm following this thread to see how minimal folks can get their steering systems.
Thanks for the experiments and information!

Thanks and good health, Weogo