Diagnostic-Gen III

[LKLD]

A ride last weekend, and the bike acted a bit strange. Cruise would activate (light came on), but unable to engage. I pulled up on rear brake, pushed out front brake, but nothing. Turned it off, and back on, still nothing. Tried different gear...nothing. So I rode without it, when about an hour later the ABS light was flashing...constantly. We stopped for a drink, cranked the bike up, and took off. Still no cruise, but no ABS light blinking either. Today I decided to pull out the service manual.

Now, I've never had a reason to do a diagnostic check before, so this is all new to me.
So looking at the service manual, it says to "disconnect the wire harness coupler from fuel pump.", before doing a diagnostic check. I assume that's under the tank (?). If so, how can I tell?

N00b

[sickchilly]

Yes, pump is in tank, connections are on the bottom of it. From your description, I'm going to guess you have a dirty or failing wheel speed sensor.

[LKLD]

Ok, got the fuel pump disconnected.

Now to the real confusing stuff.

I went through all of the "Diagnostic code: sensor operation table" and this is what I found. I'll only show the ones that didn't show normal operation according to the SM.

61) 14,19, 30, 69, and 90

62) 05

67) 02

82) all off

83) all off

So I checked the brake lights in normal mode, and nothing. Checked fuse (visually) and light bulbs (same), and all appear good. Went in diagnostic again, and 80 & 83 are both all on now.

I'm confused as to what I should check/do next.

[raYzerman]

The clue is in code 69 - No communication from wheel ABS sensors, can't detect speed, can't set cruise, ABS light may come on.
By the number of posts I see on this (here and other places), it seems Gen3's have a sensitivity with the sensors. Whether that means excess gap or not enough gap to sensor wheel I don't know, BUT, the slightest of aluminum corrosion can cause issues if the sensor gets slightly grounded.

Remove the wheel sensors, clean them up and the holes they mount in. Apply silicone grease (sticky and won't wash out) to the sensor and wipe a wee tad on the inside of the the hole in the adapter, make sure they can seat fully.

BTW, you didn't have to unplug the fuel pump, just put sidestand down in gear, pump will not run.

Codes are on 9-5 of the manual... a couple may have been stored earlier while you were attempting to engage cruise, clear them all. Scroll to 62 and cycle Start/Stop switch to clear, should now read 0. Go for a ride, check it out. Check for codes again..... hope that made you all good.

[LKLD]

Ok, so I'll look into wheel sensor(s) tomorrow (thanks SC & Ray). But does the lack of brake light have any bearing, or unrelated?
I'm wondering why 82 & 83 show all off,then all on later. Is this a short of some sort?

[raYzerman]

Could be a brake light relay, but (excluding that) if the light is off it would mean cruise can engage, but would not cancel. Some have had sensitive front brake and clutch switches (no adjustment, have to tweak yourself). Perhaps remove them and check with a meter they are working, then re-install and check operation. Brake switch I believe is actually two switches........ do brake lights come on with the brake pedal? If not, then it's point to relay (under the seat tray).

[LKLD]

Ok, did wheel sensors, which appeared remarkably clean, no change.

Checked diagnostic again on 82 (CC cancel circuit) & 83 (Front brake light switch and rear brake light switch) and still 82 is on for all sequences (clutch, f. Brake, r. Brake, and throttle), as is 83 (f. Brake and r. Brake). Disconnected the Admore wiring harness, to see if it was the cause...no change.

So on to the brake light connector (switch?). How, precisely, do I test it?

P.S. I edited previous posts to show 82 instead of 80.
80 & 81 both work (CC Res+ and Set-, respectively)

[LKLD]

Ok, so I took the spring off of the switch at the master cylinder, and turned on the bike, then pulled down on the spring, and the brake lights lit up! Put it back together, go into diagnostic mode again, do 82 & 83 again, and all checked out correctly.

So, the only differences are:
1) I cleared the codes. I did it before, but I don't think they cleared.
2) I left the Admore harness unplugged.

The Admore had been working (added in early April) without an issue.

Could clearing the codes have fixed this brake light issue, or is the harness more likely? I'm hesitant about hooking it back up now.

Going now to put it all together and go for a test ride, and see if the CC will engage.

[raYzerman]

Not 100% sure if an uncleared code will cause an issue, it may work yet keep the stored code. Best clear it, it will only come back if the condition was not corrected. Sounds like you're getting somewhere with the clutch and brake switches..... Admore shouldn't be an issue.

[LKLD]

Well, I'm going to keep the Admore unplugged for awhile, to see if it replicates. If so, then I know Admore didn't cause it.
Just got home, and the cruise now works again too.

Thanks for the help/replies raYzerman.

[ionbeam]

Just a wild thought. The Gen III has two relays associated with the rear brake circuit and can turn on/off at slightly different points. All FJRs are subject to the brake pedal sticking, even if just slightly and the brake pivot needs to be cleaned and lubed regularly. Now, if the rear brake pedal were to just slightly stick and not return fully upright.... If the symptoms return, hook your toe under the brake pedal and lift. Or, simply pull the foot peg, clean & lube the pivot. The advice is worth what you paid for it

[LKLD]

Just a wild thought. The Gen III has two relays associated with the rear brake circuit and can turn on/off at slightly different points. All FJRs are subject to the brake pedal sticking, even if just slightly and the brake pivot needs to be cleaned and lubed regularly. Now, if the rear brake pedal were to just slightly stick and not return fully upright.... If the symptoms return, hook your toe under the brake pedal and lift. Or, simply pull the foot peg, clean & lube the pivot. The advice is worth what you paid for it

I noticed the rear pedal having about an 1/8", or so, of extra movement when pulled up, so I cleaned and lubed it a month or more ago, which eliminated it.

I'm wondering now, could this be a sticking switch, at the master cylinder? If so, would silicone spray be ok?

[sickchilly]

I would use a dry graphite spray for the mechanical bits, or Caig DeOxIt for the electrical contacts.