Turbo3
Gold Member
Posts: 1796
Joined: Mon Jul 19, 2010 8:34 pm
Delivery Date: 12 May 2011
Leaf Number: 002191
Location: San Jose, CA

Re: Warning: Defective Konnwei KW-902 on the market

Sat Apr 08, 2017 5:57 pm

Would you be willing to open up your new one to see if it has the old or new circuit board inside?

The old one uses separate wires to the display panel.

The new one uses a single flat cable.

(I have no idea why my email address is appended to the end of the quote. I did not put it there.)

chirpyboy wrote:Wow, I bought one off eBay recently and had this same problem (paired with phone but sent no valid data... eventual I-key error & T/M System Malfunction).
I returned it for a refund, and bought another off Amazon which works.

I wish I hadn't sent the bad one back already so I could check its resistance. The good one is 120ohm as expected.

ones I bought:
bad: http://www.ebay.com/itm/141978657396
ok: http://www.amazon.com/gp/product/B01LNJ77YI B01LNJ77YI

cliff
Posts: 104
Joined: Mon May 13, 2013 10:36 am
Delivery Date: 15 Sep 2012
Leaf Number: 022673
Location: Federal Way, WA

Re: Warning: Defective Konnwei KW-902 on the market

Sat Apr 08, 2017 6:14 pm

The 2012 service manual shows that when the VCM is disconnected that
measured resistance on the CANBUS side is 120 ohms(seeing the BCM),
but when disconnecting the ABS unit the resistance seen on the CANBUS
side is 60 ohms(seeing both VCM, and BCM). This would agree with terminations only on the 2 ends.
There are 11 controllers on the car-can side, so if each has a 120 ohm
resistor, then the resistance seen would be 11 ohms. This is much less
that 20 ohms, so that adding a parallel 20 ohms would have a small effect
on load (but of course would add a reflection).

Turbo3
Gold Member
Posts: 1796
Joined: Mon Jul 19, 2010 8:34 pm
Delivery Date: 12 May 2011
Leaf Number: 002191
Location: San Jose, CA

Re: Warning: Defective Konnwei KW-902 on the market

Sat Apr 08, 2017 6:39 pm

cliff wrote:The 2012 service manual shows that when the VCM is disconnected that
measured resistance on the CANBUS side is 120 ohms(seeing the BCM),
but when disconnecting the ABS unit the resistance seen on the CANBUS
side is 60 ohms(seeing both VCM, and BCM). This would agree with terminations only on the 2 ends.
There are 11 controllers on the car-can side, so if each has a 120 ohm
resistor, then the resistance seen would be 11 ohms. This is much less
that 20 ohms, so that adding a parallel 20 ohms would have a small effect
on load (but of course would add a reflection).

Yes, you are correct. I should have said every ending node.

Almost all OBDII adapters have a 120 ohm resistor. Exceptions I have found are ones by GoPoint, PLX, Vgate and the Consult 3+ which have no resistor.

chirpyboy
Posts: 28
Joined: Wed Jan 11, 2017 4:30 pm
Delivery Date: 11 Jan 2017

Re: Warning: Defective Konnwei KW-902 on the market

Sat Apr 08, 2017 7:12 pm

Turbo3 wrote:Would you be willing to open up your new one to see if it has the old or new circuit board inside?

The old one uses separate wires to the display panel.

The new one uses a single flat cable.


Sure. Just checked and my new one has separate wires.

I had actually opened the bad one before returning it, because I heard something loose inside thinking that might be the problem (it was a tiny ball of solder). I remember it looked different and had a little flat ribbon cable.

Turbo3 wrote:(I have no idea why my email address is appended to the end of the quote. I did not put it there.)


This forum seems to do some hiding of Amazon links; somehow it sucked in your email? :?

Turbo3
Gold Member
Posts: 1796
Joined: Mon Jul 19, 2010 8:34 pm
Delivery Date: 12 May 2011
Leaf Number: 002191
Location: San Jose, CA

Re: Warning: Defective Konnwei KW-902 on the market

Sat Apr 08, 2017 8:07 pm

So it might be that all new manufacture with the new circuit board and the flat cable have the 20 ohm resistor.

This is pointing to a basic manufacturing error in the use of 20 instead of 120 perhaps on the assembly instructions or a miss read of the documentation used to load up the parts.

tbear2001
Posts: 18
Joined: Fri Mar 03, 2017 6:56 am
Delivery Date: 04 Mar 2017
Leaf Number: 333614
Location: Montgomery, AL

Re: Warning: Defective Konnwei KW-902 on the market

Sun Apr 09, 2017 9:04 am

Bought this a few weeks ago based on LeafSpy recommendation, but it would never stay connected so I tried another brand BATX. I just checked and it has the 20ohm resistor and I opened it up and it has the flat ribbon cable. Returning today to Amazon as defective.
2015 Glacier White Leaf S QC - Certified Pre-Owned - 2017-03-04 - 20,272 mi.
2017-03-13: AHr=55.42 SOH=89% Hx=83.64% 20,756 mi 83 QCs 648 L1/L2s

Snlj
Posts: 15
Joined: Thu Mar 02, 2017 12:55 pm
Delivery Date: 20 Mar 2017
Leaf Number: 416281
Location: Madison, WI

Re: Warning: Defective Konnwei KW-902 on the market

Sun Apr 09, 2017 4:25 pm

Confirmed! The replacement Konnwei KW902 scanner I purchased to replace my previous, malfunctioning unit only shows 20 ohms across the two pins you highlighted in your picture. Thank you for finding this out! I'll get this returned immediately.

AdamFist
Posts: 9
Joined: Sat Nov 30, 2013 9:23 pm
Delivery Date: 30 Nov 2013

Re: Warning: Defective Konnwei KW-902 on the market

Mon Apr 10, 2017 6:49 pm

This thread was helpful and timely since I received my Konnwei KW902 yesterday. I'm returning it to Amazon. In the meantime, does anyone have a recommendation for an alternative ODB2 scanner that works?

Thanks,
Adam

Turbo3
Gold Member
Posts: 1796
Joined: Mon Jul 19, 2010 8:34 pm
Delivery Date: 12 May 2011
Leaf Number: 002191
Location: San Jose, CA

Re: Warning: Defective Konnwei KW-902 on the market

Mon Apr 10, 2017 10:25 pm

AdamFist wrote:This thread was helpful and timely since I received my Konnwei KW902 yesterday. I'm returning it to Amazon. In the meantime, does anyone have a recommendation for an alternative ODB2 scanner that works?

Thanks,
Adam

The currently available test version of LeafSpy Pro supports the newer Bluetooth 4.x LE as will the next official releases of all versions of LeafSpy which I hope to start rolling out within the week.

There are two supported Bluetooth 4.x LE OBDII adapters. The LELink and the PLX Kiwi 3 with the LELink from Amazon being the cheaper of the two. The LELink is what I use and works with the iOS version of LeafSpy and will work with the next release of the Android versions of LeafSpy.

Bluetooth 4.x LE being a low power adapter will result in less drain from your 12v battery when the Leaf is off. There is also no pairing required.

Anyone with the Android version of LeafSpy Pro can try the latest test version using this link.
https://play.google.com/apps/testing/com.Turbo3.Leaf_Spy_Pro

Turbo3
Gold Member
Posts: 1796
Joined: Mon Jul 19, 2010 8:34 pm
Delivery Date: 12 May 2011
Leaf Number: 002191
Location: San Jose, CA

Re: Warning: Defective Konnwei KW-902 on the market

Mon Apr 10, 2017 10:41 pm

AdamFist wrote:This thread was helpful and timely since I received my Konnwei KW902 yesterday. I'm returning it to Amazon. In the meantime, does anyone have a recommendation for an alternative ODB2 scanner that works?

Thanks,
Adam

I forgot to ask. Are you returning because it measured 20 ohms or just because it is a Konnwei KW902?

If you don't have an ohm meter you can tell if it is new manufacture by opening it up and seeing if it has a flat cable to the top display board. If it is new production it is probably bad. Measuring 20 ohms is of course the gold standard for defective.

Return to “LEAF CANBus”