Heated Grip Problem

[Bobby]

So I replaced the hard original grips on my 2013 k13s and now the heated grips don't work. I've done this on two other k bikes without a problem and was careful this time in cutting off the old ones. I think I may have broken a wire when sliding the left grip on. I have yet to check for error codes with the gs911. Could it be something simple that I'm overlooking or do I need to remove the new grips and test the wires?

[802Mike]

Both sides don't work?
Stupid question but, are the grips thicker and maybe it doesn't get hot as fast?

[R111S]

Hi Bobby, I'd hook up the GS-911 before going any further. If I'm correct the Heating Element should be 15 Watts which would be ~9.6 Ohms (thanks HenkPenk) of Resistance when measured between the 2-wires and not connected to the Circuit.

I'll put a set of Foam Grip over the OEM Heated Grips. Heat comes through just fine.

[justjoe]

According to Occam's Razor, you are most likely suffering from damage to the heating element during removal of the grips. I think there is a plug where you can begin your search.

[Bobby]

Both sides don't work?
Stupid question but, are the grips thicker and maybe it doesn't get hot as fast?

That's correct both sides don't work. I took a long ride and played with the on/off switch and left it on for a long time, and nothing.

[Bobby]

Hi Bobby, I'd hook up the GS-911 before going any further. If I'm correct the Heating Element should be 15 Watts which would be ~1.25 Ohms of Resistance when measured between the 2-wires and not connected to the Circuit.

I'll put a set of Foam Grip over the OEM Heated Grips. Heast comes through just fine.

When I get back home I will check it with the gs911 and a multimeter. Yeah, foam grip would have been a safe option.

[Bobby]

According to Occam's Razor, you are most likely suffering from damage to the heating element during removal of the grips. I think there is a plug where you can begin your search.

Yeah, good old Occam. I removed and replaced the left grip first, so that is likely where the problem is. But before I cut that grip off I will pull back the end of the grip and test the continuity. Is there anyway to repair a broken wire that small? Or does one just replace the whole heated grip ?

[R111S]

If you could solder the broken wire it would be at risk of un-soldering due to the heat.

[jzeiler]

Solder melts at 370 F I don't think the grips get that hot.

[henkpenk]

Check this one: https://www.youtube.com/watch?v=-2uKp0vgD4Y

[R111S]

Nice video you shared Henk. Thanks. Interesting to see a soldering repair can be made. Wish he'd told what the resistance value is on a known good heating element?

Since he substituted a stranded wire for the missing heating element length, the total resistance will be slightly lower, and thus higher current flow. There is a limit to how much length of the heating element that can be replaced with stranded wire but it looks like a short section so likely OK.

[Bobby]

Ok. I'm back from my house hunting trip to Oregon and in the garage investigating this heated grip problem. I tested the continuity of the wires that wrap around the grips and they're competent. I then checked the bike with the gs911 and found the following fault code: "41740 heated grips, short circuit. The fault is not present now." So I cleared the fault code, started the bike, and still no heat coming from the grips. I used the gs911 again and got the same fault code. The only thing I can think of is that I have a loose wire inside the left hand Switch Cluster. Any suggestions?

[henkpenk]

Bobby, I sure hope it is not the ZFE that's at fault.
I had a LAMPF message on the dash telling me the right indicator bulb was out. It wasn't. GS911 told me the circuit was open. It wasn't. Very annoying!
I checked everything but found nothing wrong with the wiring. Finally I talked the dealer into loaning me a spare ZFE they had.
Bingo!
(I bought a second hand ZFE from a guy in Austria. Problem solved. For 100 euro it is a steal compared to the 800-plus for a new one from the Germans. Also, when replacing the ZFE I discovered that one ot the small rubber silencing blocks that protect the ZFE from vibrations was missing so the ZFE made at one corner hard contact with the bike frame. Perhaps that killed the first one.)

[Bobby]

I think the fault code was listed under the ZFE....because that cpu runs the heated grips. But that is the only fault I have, so the ZFE itself is not damaged. I may have to take the bike to my trusty BMW technician to figure out.

[henkpenk]

That's the trouble with the ZFE: it cannot diagnose it's own power output. When something is wrong it assumes that it must be the wiringharnass further down the line or the power user (in this case the grips) itself.

[R111S]

ECMs are "blind" with respect to the physical location of a Fault in any Wire Harness/Load/Sensor/Switch. It boils down to the Integrated Circuit Chip that is monitoring the output or input circuit. It's "looking" at the current or voltage, as the case may be, "seen" within the Chip itself.

To locate failures within Wiring Harnesses, the Aircraft Industry uses TDR (Time-Domain-Reflectometry) to find shorts/opens within, due to the long length of wires on Aircraft. TDR helps to physically locate these wiring failures much quicker. For our Motorcycles it's not practical nor cost effective to have TDR.

Since your Grip Heater Fault is "41740 heated grips, short circuit" the short may lie anywhere between the ZFE Connector and the Grips. Try wiggling various parts of the harness between the ZFE and the Grips while monitoring for a change in the Fault Code status. If your wiggling finds a specific section of harness that consistently makes the status change then you've located the failure within the Wire Harness. At this point you can expose the wire and make repairs.

Connectors can also suffer a short circuit failure if there are conductive contaminates inside that short terminals together. Visually inspect all connectors to see if contamination is the culprit. If that's the problem, use Brake Cleaner to thoroughly clean out the connector terminals and body.

[Bobby]

The only part of the heating circuit I touched was when I removed and replaced the grips. So if the heating wires are competent, which they appear to be based on my continuity test, then the problem likely lies in a wire just outside one of the grips. The wires leading from the grips into the switch clusters appear to be stable (i.e., they didn't move or come loose when I pealed away the old grips). I'm not particularly good with electronics so perhaps my continuity test was incorrect and I actually have a broken heating wire. That's the most likely scenario. Like Joe said, Occam's Razor may apply here.

[R111S]

Quote: "perhaps...I actually have a broken heating wire"...this would elicit an "open circuit" Fault Code..not the "41740 heated grips, short circuit" Code.

[cabnfvr]

True dat, not an open circuit. If the ECU is turning off both grips then you have a short to ground, and that is what the fault is telling you. An open circuit at the grip would only make the one grip not work, not cause failure in both. You're going to have to go back is so unplug one grip and see what happens. If the other grip gets warm then you've at least found the side with the fault. If nothing happens plug the grip back in and unplug the other side. .