Warning: Defective Konnwei KW-902 on the market

[Turbo3]

I need to send the engineer who is looking into this a picture of the circuit board with the bad resistor. Unfortunately I have returned my defective one to Amazon.

Can someone who has one with the 20 ohm resistor take a picture of the circuit board and send it to me?

 

[des28]

Hi,

Thanks for posting this, just tried mine and it's 20 ohms. Got it from aliexpress. Haven't used it yet as my Leaf is still to arrive (just got loaded on a ship in Japan tonight!)

I would open it up and post a picture for you, but can't get into it as don't have the right size hex bit to do so. Should be able to if I take it to work tomorrow though.

If it is just the wrong resistor I'll just replace it myself.

Cheers,
Des

 

[AdamFist]

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.

I don't have an ohm meter (and didn't read this reply until after I had processed the refund, placed the KW902 into an envelop and into a mailbox). I'm returning it because after I plugged it into my 2015 LEAF S, my dash displayed 2 alternating error messages "I-Key {something something}" and "T/M System Malfunction" while KW902 was plugged in. LEAF was making funny noises and I (gracefully) unplugged the KW902. I was able to start the LEAF but it displayed the yellow "!" symbol which cleared itself after driving around for a minute. No permanent damage, I hope.

Adam

 

[Turbo3]

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.

I don't have an ohm meter (and didn't read this reply until after I had processed the refund, placed the KW902 into an envelop and into a mailbox). I'm returning it because after I plugged it into my 2015 LEAF S, my dash displayed 2 alternating error messages "I-Key {something something}" and "T/M System Malfunction" while KW902 was plugged in. LEAF was making funny noises and I (gracefully) unplugged the KW902. I was able to start the LEAF but it displayed the yellow "!" symbol which cleared itself after driving around for a minute. No permanent damage, I hope.

Adam

From what you describe you definitely had one with the 20 ohm resistor in it.

 

[Turbo3]

I have received a nice hi-res picture of the inside of the Konnwei KW-902 and sent it on to the seller to give to the engineer. Also added it to the first post.

I think you can just remove the 20 ohm resistor and it should work. Please report back if you have done this.

 

[des28]

Ha, I'd just taken pictures and came back here to post them!

Wouldn't you need to replace that with a 120 ohm resistor rather than just removing it?

 

[Turbo3]

Ha, I'd just taken pictures and came back here to post them!

Wouldn't you need to replace that with a 120 ohm resistor rather than just removing it?

A few OBDII adapters I have tested do not have a termination resistor. This includes Nissan's Consult 3+.

 

[des28]

A few OBDII adapters I have tested do not have a termination resistor. This includes Nissan's Consult 3+.

That's a little odd. I guess that is relying on a similar resistor at the other end to do the job instead. I did actually look up the datasheet of that particular chip and noticed they described a test circuit that used a 60 ohm resistor between the 2 pins, I guess that makes sense if in normal operation there is a 120 ohm at each end (which are effectively in parallel giving 60 ohm in the running circuit).

Cheers,
Des

 

[jtselkain]

I am very happy to hear that KW902 from aliexpress is defective. I measured that my kw902 has 20 ohm resistor. I got it today and it put my leaf in error state. Fortunately the error vanished after 2 hours.

 

[Turbo3]

I removed the 20 ohm resistor and the Konnwei KW-902 now works in the Leaf.

 

[Jedlacks]

I measured the resistance on mine and it read 121.2 ohms. I had it plugged in all the time until a few weeks ago, because it was sucking my battery down. With it plugged in my resting battery level was at 12.45+/- volts, and that caused the Nissan Connect not to work. I since put the battery on a slow charge for a few hours and my "first world problem" is now behind me

 

[DarthBane]

Hi Turbo, this is Frank (the 1st unlucky one to have a defective Konnwei, we talked via email).
So I have 2 bad ones now, one from Aliexpress and one from Amazon. I saw the fix, removing the little resistance you show on the picture... I did that, but, before I go ahead and brick my Leaf, I'd like to see if I did this correctly:
1st off, I could barely see anything there, we are talking microscopic almost! Anyways, I saw something, and flicked it off with my fingernail, and it came out. Really small stuff.
Then I re-tested the resistance, and now the needle does not move at all when testing pin #6 to pin #14. Is that a good sign, or should it have gone back to 120 ohms?
If this is right, then I will plug it in and see what happens. I'll probably fix the 2nd one too instead of returning it, I could use it with Torque on my other car I guess.
Thanks for all the help!

 

[Turbo3]

Hi Turbo, this is Frank (the 1st unlucky one to have a defective Konnwei, we talked via email).
So I have 2 bad ones now, one from Aliexpress and one from Amazon. I saw the fix, removing the little resistance you show on the picture... I did that, but, before I go ahead and brick my Leaf, I'd like to see if I did this correctly:
1st off, I could barely see anything there, we are talking microscopic almost! Anyways, I saw something, and flicked it off with my fingernail, and it came out. Really small stuff.
Then I re-tested the resistance, and now the needle does not move at all when testing pin #6 to pin #14. Is that a good sign, or should it have gone back to 120 ohms?
If this is right, then I will plug it in and see what happens. I'll probably fix the 2nd one too instead of returning it, I could use it with Torque on my other car I guess.
Thanks for all the help!

No, it will not be 120 ohms. I just measured my working one without the resistor and get about 27.5 K ohms. I think you are OK to install it.

 

[DarthBane]

Ok, confirmed working after removing the 20 ohms resistance. Changed the door unlock method and it worked, great, thanks a lot for all the info! Now I have 2 working Konnwei units!

 

[chivalryx]

FYI. The KW-902 Wifi versions are also affected. Unfortunately the board is very different from the original post, so I'm unsure which resistor to remove. Didn't help that the build quality was poor, so one wire had come loose of the solder point and was just hanging there...

 

[des28]

You may be able to follow the tracks from the pins, or look for this same chip as in the attached image, resistor is likely to be right beside it on pins 2/3 as it is with this one. You can measure the 120 ohm / 20 ohm right at that point too.

Cheers,
Des

 

[Battlewind]

First post!

First off, thanks for the recommendation on the adaptor. Second, thanks for the warning on this. I too ordered one from Amazon and it came in with a 20 ohm resistor.

As I read this, my options are to either return it or desolder the 20 ohm resistor correct? If I do return it, how many time have others done this in the past before getting a good one?

Thanks!

 

[Battlewind]

I ended up sending it back for a refund. I couldn't get it to work properly. I had an older ELM327 that ended up working fine once I turned off the car's bluetooth. Now I have to figure out why they won't work together.

 

[baustin]

I ended up sending it back for a refund. I couldn't get it to work properly. I had an older ELM327 that ended up working fine once I turned off the car's bluetooth. Now I have to figure out why they won't work together.

Your phone can only connect to one device at a time. The bluetooth connection to the car is automatic when it turns on. This prevents the connection for LeafSpy from working. I use a separate tablet for LeafSpy, so that I don't have that problem.

 

[magico13]

Your phone can only connect to one device at a time. The bluetooth connection to the car is automatic when it turns on. This prevents the connection for LeafSpy from working. I use a separate tablet for LeafSpy, so that I don't have that problem.

That might be true for their phone, but is not a general truth. LeafSpy works fine with my phone also playing music through the car while also connected to my watch. Bluetooth is supposed to work with multiple devices at the same time, at least as long as they have different functions.