Help me save a Giant Lafree Lite

[flapajack]

I posted this in the wrong place, so have repost it. Could an administrator please delete the identical post within classified, thank you.



Well, whilst waiting for my new Kalkhoff, I went and picked up a second hand Giant Lafree Lite. It was meant to be a tester for the missus to use as school run with a 4 yo on the back and the older on his own 20" bmx bike. The journey isn't far (about 0.7mile) but quite hilly.

After a full-ish service and some plastic mending, the bike looks quite presentable. Everything work as it should, although I snapped the bolt holding the AXA nurse lock as I need to remove it to fit the toddler seat. The bike still pull strongly although, like many Lafree, the battery is probably in need of some service. It did have 4 led on when pick up and earlier today done a 10 miles hilly trip so not too bad (I guess). I charge it once before since purchase and it came back to only 3 led, needing a further cycle before settling down at 4 led.

After the trip back I put the battery back into charge and the charging stops after only 1 led. I plug it back in and it rises to 2 led after a couple of hours. Repeat this again and it came up to 3 led. Not sure whether this is an issue with the battery or the charger.

So here's are my questions:

1) does anyone still have a copy of the manual for the charger? I am curious as to what I should expect and also not sure what the battery "refresh" option is for and how to start it.

2) does it sounds like the battery is on its way out, or is it the charger? Any way to check/confirm?

3) I read flecc did a recall of the Lafree's 24v battery (from forum searches) but the link seems to have died. Is the instruction still available?

4) the battery seems to have little circle stickers stating 01, 02, 03, 04, 05, 07, 08, 09 on. This seems to be servicing stickers so it looks like the battery was well look after, but this has stopped a few years back. Any actions I should/could do at this stage to "service" the battery (apart from keep using it)?

As this is a "tester bike" a new ebike is likely to be on the card although it will be very sad to see this lovely Lafree going to the recycling centre - especially when it still works so well. Any help and advice would be greatly appreciated. I got this week off work and is quite spanner-handy so can do most things - except probably getting too technical with electrics.

Thanks

 

[flecc]

It is the charger faulty, a well known and common problem on these Panasonic chargers supplied with the Lafree. They aren't repairable having deep encapsulated circuit boards, so must be replaced.

The official replacement is very expensive, but a suitable one is listed on this webpage on my website. If buying from this US source, when going through the web buying stages make sure you alter the postage from the expensive UPS default to USPS to keep the cost down.

I don't know of a UK or EU source for a suitable NiMh charger.

The number labels on the battery are not for servicing. The appropriate one was meant to be removed by the dealer to indicate the year the battery was sold.

 

[flapajack]

Fantastic flecc, exactly what I was looking for thanks!

Is there a way to check whether the panasonic charger is faulty (most likely although would prefer to be sure before spashing out for a replacement)?

 

[flecc]

Your symptoms confirm it's definitely that. Part charge, then restarting the charge gains a bit more, and each repeat of restarting the charge adds a bit more until eventually a full charge might be reached after about five or more restarts.

All typical of what happens. With no access to any of the circuit board no testing is possible. My suspicion is that a defective zener diode may be the problem, having seen similar symptoms on HP chargers with a defective zener diode, but that is just a guess by association.

Having found the problem occurring, Panasonic temporarily changed to a very good charger from Metco, eventually launching a new design of their own for late Lafree models. But that also failed at times!

 

[flapajack]

Thanks flecc, that's all the reassurances I need.

 

[flapajack]

Wiring colour

Well, the Powerstream charger finally arrived (took quite some time and a few calls, but satisfactorily resolved in the end). I am diligently going trough flecc's instructions on his Giant Lafree web-site to install a new flylead but a small problem crops up.

The charger came with a XLR female plug but the wiring colours are different. Instead of red, white & black for pins 1,2 & 3 respectively I have blue, brown and black. Also the position of the pins are reversed (well, if you go by the direction the numbering are printed on the plug although if you turn it up-side-down it seems to match ok) - see photos. I dont want to solder in the cables and then find that it is wrong - could blow up the battery, the charger or both! Also, without a bettery connected I cannot tell from the voltage across the pins using a multimeter - it just gives some strange, small voltage reading in the region of 0.5/6 V and not 24V+ ish.

Questions are:

1) Is the pin numbering universal (ie pin #1 on the NTC is the same as pin #1 on the XLR)?
2) Am I correct to assume therefore that my blue is the same as red (ie live), and brown, therefore, being the white (sensor - green or yellow as per flecc's diagram) etc?

Thanks in advance for any assistance.

 

[flecc]

This is a common problem with Chinese production, colour codes varying. I haven't seen this combination of colours before on these, but the brown is more likely to be the positive, as shown on my illustration, with blue as the sensor, though I can't guarantee that. The charger won't show correct voltages until the thermistor or a suitable resistance is in the sensor circuit.

Ignore the pin numbering, the Panasonic arrangement is non-standard anyway. Just try the connections as I suggest, since the charger won't issue any voltage until the sensor is correctly connected between sensor voltage and earth, so no damage will result. If that doesn't work, try different connections until successful.

 

[flapajack]

Thanks flecc, that is very reassuring.

I will connect it up using some wires and crocodile clips to test before permanently solder them together.

From your explanation then, can I just re-check my understanding.

Charger <---> Giant connector (per your diagram)
Brown ----- Brown
Black ----- Blue
Blue ---- Green/yellow

 

[flecc]

That's it, I think it the most likely. If that doesn't work, next try blue to blue and black to green/yellow, leaving brown to brown.