MK6i controller

[william]

The MK6i controller on my Invacare TDX SP will only move the chair in two drive modes, D1 and D3. In Ramp mode the tilt and recline function of the chair is activated even though this has a separate controller. Also, the MK6i does not accurately show the state of the charge – it indicates that the batteries are consistently full even when they are empty.
Any ideas???

[Burgerman]

No experience of that controller.

But battery meters measure voltage. A high resistance battery can read a perfectly normal voltage until you try to take power out. So it seems dead. But the voltage recovers straight away. So the meter reads full still.

Gel batteries that are old are a good example of this. Especially cheap (read non MK or other quality brand). Most gel batteries start off higher resistance than AGM batteries but get worse with use/age.

[JoeC]

You will need access to a programmer, or somebody who has a programmer and knows what they are doing will need to fix it. It's a shame that so many wheelchair vendors take a chair from the factory, look at a clipboard for things like color and rough measurements, then hand over the chair like it's exactly right.

There are a hundred ways to program a chair to behave the way you want, need, and expect. Whoever set that chair up obviously didn't consult you or explain it.

The battery gauge *may* be able to get a slightly better grip on reality with a programming tweak, I don't know exactly what changes are available. It will never be as exact as the battery gauge on a laptop. Lead based batteries have a capacity that varies depending on how they're used, it's much less predictable compared to lithium batteries. The way they're used is unpredictable, too. Some times of driving can demand a lot from the batteries, and other conditions are not as demanding.

[william]

Many thanks! The batteries should be MK, but they have been on the chair since new, 18 months ago.

A programmer?? Are these generic devices or are they specific to a particular controller? Do you know if they are easily available and can they be bought online?

I bought the chair second hand from the US and shipped to Mexico where I live. I doubt if there is much expertise here in setting it up.

Thanks again

[Martin O Refurbisher]

Have you discussed the problem with the seller? They might be able to help.
From your response, you clearly need hands-on help.

Invacare list 2 dealers in Mexico, see:

http://www.invacare.com/cgi-bin/imhqprd ... ts.jsp?s=0

It may be worth trying these for help.

Programmers are hand-held or PC based, and specific, in termsa of cable and software, to a specific make/range of controller. They allow advanced diagnostics and adjustment of the parameters.

If you do not already have hte owners manual, which should give some help, you can download a copy from:
http://www.invacare.com/cgi-bin/imhqprd ... ch.jsp?s=0
Best,

Martin

[gac3rd]

Here is a link to a MK 6i programmer on eBay just to give you an idea of what one looks like.

http://cgi.ebay.com/Invacare-wheelchair ... 500wt_1156

It connects to the controller via a cable, and it allows the user to change various parameters in the controller.

Here is a manual for the MK6i electronics including a section on the programmer.

http://www.invacare.com/doc_files/1141471.pdf

As you can see, this might be a bit overwhelming for a beginner. Also, the programmer will not tell you anything about battery voltage or condition. This is a based on a quick pass through the manual as well as some experience with a MK IV programmer. The MK 6i has a lot more options for seating and controls, but the basics have not changed much.

After 18 months, it may be time to replace batteries. You need to get to someone competent to make a reasoned judgement about what is going on.

[william]

Many thanks for the very useful inks. I had hoped there was a simple fix, but it seems we have to go the long way round.

[woodygb]

http://www.youtube.com/watch?v=y5xCj0xA5NU

[william]

An excellent video - even I could follow it! Many thanks.