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Heated Grip--left side fail

mgordon

New member
Hey all, my 98 R1100r left side heated grip has failed. I've got proper voltages at the rocker switch (hi-11.5v/low 9.5v) and at the wires to the element in the grip. Since buying this bike from the PO, I've had to clean/lubricate the switch internally, and only just realized that it was 3-way, as it was physically stuck from corrosion.

I've also tested for continuity between the leads at the grip, which was good.

So if I've got voltage and continuity through the circuit, where is the failure? I guess the one last thing to do is check the connection at the main wiring harness under the tank, correct?

Thanks!
 
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Did you check resistance through both sets of grip heater leads, comparing the functional side to the non-functional side?
 
I did not check resistance at the other side and am loathe to since it is working perfectly, and don't want to mess with it!
 
I did not check resistance at the other side and am loathe to since it is working perfectly, and don't want to mess with it!

No sense of adventure, eh?
Hopefully someone knows what they should be and can give you a value to check your failed side against.
 
Took the tank off, cleaned the connectors, checked for continuity and voltage and all good. Must be the grip element!
 
Took the tank off, cleaned the connectors, checked for continuity and voltage and all good. Must be the grip element!

Well, go to the connector where the left grip plugs into the harness again. Re-verify voltage at that connection to a known good ground. Then use a continuity tester to verify the ground wire on the harness side is a good ground return path.

Then use an Ohm meter to read the resistance from one pin on the grip side through the grip to the other pin on the grip side.

These three tests tell what is going on.

1. 12v at hot pin on harness side: yes or no.
2. Ground path on harness side: yes or no.
3. Continuity through the grip with high resistance: yes, or reading open.

If one fails backtrack through the harness.
If two fails then backtrack till you find where the ground is lost.
If three fails the grip is shot.

My guess is #2.
 
Thanks Paul! Need some clarification:

How do I verify the ground wire on the harness side exactly?

Then, do you mean measure resistance between both pins at the grip end, where they connect to the heater element wires in the grip? I've already done that and gotten high resistance.





Well, go to the connector where the left grip plugs into the harness again. Re-verify voltage at that connection to a known good ground. Then use a continuity tester to verify the ground wire on the harness side is a good ground return path.

Then use an Ohm meter to read the resistance from one pin on the grip side through the grip to the other pin on the grip side.

These three tests tell what is going on.

1. 12v at hot pin on harness side: yes or no.
2. Ground path on harness side: yes or no.
3. Continuity through the grip with high resistance: yes, or reading open.

If one fails backtrack through the harness.
If two fails then backtrack till you find where the ground is lost.
If three fails the grip is shot.

My guess is #2.
 
Thanks Paul! Need some clarification:

How do I verify the ground wire on the harness side exactly?

Then, do you mean measure resistance between both pins at the grip end, where they connect to the heater element wires in the grip? I've already done that and gotten high resistance.

Second question first. If you are getting a high ohm reading through the grip - both pins at the grip side of the connector - that grip is testing good. Do the test at the connector so you are testing the wire to the grip and the wire through the grip.

Now for the ground return path. Again, use the Ohm meter. Identify the ground pin on the harness side of the connector. It will be the one that doesn't have 12v to it, and probably is a brown wire. Measure resistance from that pin to either a good ground on the chassis or to the battery ground (negative) terminal. You should get a reading of just a few Ohms. If the reading is open you have lost the ground completely from a very bad connection or a broken wire. If you get a reading of very high resistance then that signals a dirty or loose connection.
 
Second question first. If you are getting a high ohm reading through the grip - both pins at the grip side of the connector - that grip is testing good. Do the test at the connector so you are testing the wire to the grip and the wire through the grip.

Now for the ground return path. Again, use the Ohm meter. Identify the ground pin on the harness side of the connector. It will be the one that doesn't have 12v to it, and probably is a brown wire. Measure resistance from that pin to either a good ground on the chassis or to the battery ground (negative) terminal. You should get a reading of just a few Ohms. If the reading is open you have lost the ground completely from a very bad connection or a broken wire. If you get a reading of very high resistance then that signals a dirty or loose connection.

Ok, still a little confused, thank you for your patience...If i have it right, you are saying check for resistance where the grip leads are plugged into the harness connector under the tank, since I've checked the leads at the handlebar? Or are you saying put one probe on the grip/handlebar lead, and one on the grip side at the connector to test resistance all the way back to the connector through the entire grip circuit?
 
I think this may help clarify Paul's comments - hopefully

grip%2520heater.jpg


Measuring between C and frame ground / battery negative, you should have little to no resistance.
(The same should be true between G and frame ground / battery negative - right grip heater)

Measuring between A and B should give you high resistance. (The grip harnesses should be unplugged for this.)
(The same should be true between E and F and the values should be similar - right grip heater)

Measuring between P and frame ground / battery negative should give you ~ 12V

With the switch on high, measuring between M and frame ground / battery negative gave you 11.5V.
(The grip harnesses should be unplugged for this.)
(The same should be true between D and frame ground / battery negative)
(The same should be true between D and C)
(The same should be true between H and frame ground / battery negative - right grip heater)
(The same should be true between H and G - right grip heater)

With the switch on low, measuring between N and frame ground / battery negative gave you 9.5V.
(The grip harnesses should be unplugged for this.)
(The same should be true between D and frame ground / battery negative)
(The same should be true between D and C)
(The same should be true between H and frame ground / battery negative - right grip heater)
(The same should be true between H and G - right grip heater)
 
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I am not doing anything at the handlebars/grips. I am suggesting you unplug the wire connector from the grips where it connects to the harness under the tank, usually at the front.

Now each side of that two pin connector is exposed: on the grip side and on the harness/bike side.

The brown wire is ground.

Reading Ohms from one pin to the other on the grip side is resistance through the grip wire.

Reading Ohms from the ground pin (brown wire) on the harness side to the battery negative terminal tells whether that is a good ground.

And of course, reading VOLTAGE or using a test light on the 12v+ pin on the harness side tells if the power is getting that far.
 
I am not doing anything at the handlebars/grips. I am suggesting you unplug the wire connector from the grips where it connects to the harness under the tank, usually at the front.

Now each side of that two pin connector is exposed: on the grip side and on the harness/bike side.

The brown wire is ground.

Reading Ohms from one pin to the other on the grip side is resistance through the grip wire.

Reading Ohms from the ground pin (brown wire) on the harness side to the battery negative terminal tells whether that is a good ground.

And of course, reading VOLTAGE or using a test light on the 12v+ pin on the harness side tells if the power is getting that far.

Ok, now that is crystal clear. Thanks guys! I'll get back with results!
 
Not sure if this helps any, but a single plug on my '96 R1100RSL contained all 4 heated grip leads.

heated%2520grip%2520plug.jpg

Thanks, mine too. But i read between the lines of what Paul said, in terms of isolating the left side in the harness connector...cheers.
 
FIXED!!! Woo hoo!

Hey guys, thanks for your help. Fresh battery in the multimeter was the first step. Then I got a no-continuity reading on the grip side of the connector for the left side. With the probes attached, i found a poor connection under the grip, which I pulled back and after removing the brown tape, found a broken element wire! I stripped out a bare piece of wire and spliced/braided it on, taped it all up nice and tight and VOILA! Warm hand!!

In the meantime, I also got to inspect, re-tape and re-ziptie the wiring harness all the way along, as well as clean all connectors.
 
I am not doing anything at the handlebars/grips. I am suggesting you unplug the wire connector from the grips where it connects to the harness under the tank, usually at the front.

Now each side of that two pin connector is exposed: on the grip side and on the harness/bike side.

The brown wire is ground.

Reading Ohms from one pin to the other on the grip side is resistance through the grip wire.

Reading Ohms from the ground pin (brown wire) on the harness side to the battery negative terminal tells whether that is a good ground.

And of course, reading VOLTAGE or using a test light on the 12v+ pin on the harness side tells if the power is getting that far.

Paul --

Just a note to sincerely thank you for your concise diagnostic instructions in this thread. My right heated grip on my R1100RSL didn't work (left was fine), I followed your steps and solved the problem without damaging / destroying anything thru potentially messy trial and error (problem was a broken lead wire near the heating element -- which I knew from doing your tests. I'm guessing that was the result of a wire getting stretched during the installation of bar backs any number of years ago).

Now in the latter half of October in New Jersey, it's great having both grips hot when needed. Thank you!
 
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