[cmdrrickhunter]

Recently my Vstrom developed starting trouble. Some days it would start fine, other days it'd take a few 5second bursts of the starter before it came to life. I started to do some light diagnosis (like tossing some SeaFoam in a tank, thinking it might be the fuel injectors), but eventually it just died, leaving me stranded at work, so I've started attacking it in earnest (true to its fickle nature, it started perfectly the next day so I could take it home).

I did some forum searching. Whenever it fails to start, the FI light comes on, so I found the post describing how to put the bike into dealer mode, and got a C42 error (Ignition switch). That has been attributed to dirty contacts.

It looks like its quite an effort to get down to some of the contacts to clean them, so I'm a little concerned that the C42 could be a red herring... could it simply be saying "the idiot holding the handlebars let go of the ignition switch too early?"

Beyond the ignition switch, does anyone have any easy to check things before I start filling my garage with disassembled Vstrom pieces? I believe I can hear the exhaust put-putting when the starter is going, so the engine should be turning over. I haven't pulled the spark plugs yet.. they're probably next on my list!

 

[greywolf]

A C42 detects an anti theft device error in the ignition switch which is simply a resistor. Nothing you did could cause it. Most likely it's a marginal contact or connection causing the resistance to be excessive. Ignition switch faulty? How to repair it!

It could also be a poor connection between the switch and the ECM though.

 

[SittingDuck]

[...] I started to do some light diagnosis (like tossing some SeaFoam in a tank, thinking it might be the fuel injectors),[...]

Adding seafoam is not a diagnostic procedure; at best it's a fix and considering that most additives don't do anyting at all, what were you hoping to diagnose?

If you suspected injectors, why didn't you just check if they were getting the ECM signals properly or if they were clogged? They should be easy enough to remove...

 

[cmdrrickhunter]

Adding seafoam is not a diagnostic procedure; at best it's a fix and considering that most additives don't do anyting at all, what were you hoping to diagnose?

If you suspected injectors, why didn't you just check if they were getting the ECM signals properly or if they were clogged? They should be easy enough to remove...

Honestly? Fear. My last attempt to be more independent of my local dealership didn't go so well, so I wasn't ready to lift the gas tank until I at least had something reproducible to fix. And my theory with the seafoam was that, if the problem was just starting, a little fix like an additive could counter it, then I'd know where to attack next. From the sound of your reply, it sounds like I was hopelessly optimistic.

 

[greywolf]

If just getting the tank off is a stumbling block, see Fuel Tank Removal How to, 650 & 1000

 

[SittingDuck]

Honestly? Fear. My last attempt to be more independent of my local dealership didn't go so well, so I wasn't ready to lift the gas tank until I at least had something reproducible to fix. And my theory with the seafoam was that, if the problem was just starting, a little fix like an additive could counter it, then I'd know where to attack next. From the sound of your reply, it sounds like I was hopelessly optimistic.

You're selling yourself short; the tank comes off easily as per the ower manual's instructions (or whatever GW posted).
I like to take a couple more screws off than what the manual recommends; it makes it easier to slide the tank back in.

GW suggested your code was an ignition switch issue. all 4 wires (red, orange, orange/yellow and brown) should have continuity with the key in the on position. and red to brown only in the park position; in all other positions, everythign should be off.

 

[greywolf]

It's more than continuity. The ECM has to read the reduced voltage due to the resistor in the ignition system. If the voltage is too high or too low, a C42 fault will be displayed and the bike won't start or run. The resistor is not in the wiring diagram. It's supposed to be a secret.

 

[dancer]

Pressurized spray cans of Electrical Contact Cleaner, available through your local electrical supply company, can be a temporary or even a permanent fix. It promotes conduction where needed, demotes it where unwanted, and reaches hard-to-reach places with a nozzle extender. It rescued my tractor with a broken battery cable terminal from the back pasture a few days ago.

I'd post a photo of mine but the orange paper label has mostly torn off and it just looks like ... a can.

 

[richw]

Corrosion at the plugs as well

Unplug, examine, clean if needed, replug

dielectric grease I cheat with marine grease thick vasolene

#2 always examine the last area some ham fisted mechanic was at

My tank just comes straight back there is enough flex in the sides so it can sneak in and out

 

[cmdrrickhunter]

I got the gas tank off, and the air filter (which was actually a bit harder than I expected). That was enough to get my hand in there to unplug and plug the connector to the ignition. I haven't 100% reassembled things yet, but from the lack of an error code, it looks like that's where the problem was. I just need to do some research on the best way to clean a connector that's still strapped inside the bike!

I'm glad I came across this community with awesome people in it... I'd have been baffled when my service manual didn't mention anything about resistences.

I did come across something I'm curious about. When removing the air filter, my service manual didn't do a very good job of explaining what hoses I was removing. When I really boiled the instructions down, it came down to "remove the hoses holding the air filter down until you run out of hoses." One of the hoses looked different than the others, and I'm curious what its purpose is. This hose was the one thats larger than the others, connected by a mondo-sized hose clamp, and it went into a small chamber on the air filter body with a sponge in it (seemed kind of oily to me). The other end went down into the body of the engine right behind the coolant pump. All of the other connections I could trace and make guesses at what their purpose was, but this one has me stumped!

 

[greywolf]

The hoses to the oily sponge are crankcase breather hoses.

 

[Maco]

I had the C42 problem on mine after lubricating the sticky ignition switch. I sprayed brake clean into the ignition key hole to clean it and used pressurized air to dry. I have not had a problem since then.

 

[cmdrrickhunter]

Just an update for the next guy, after assembling and disassembling things for a few weeks, I finally decided the computer's response after the engine turned over was funny.. it seemed to reboot. Didn't like the way that behaved, and noticed the bike started perfectly when I jumped it from my truck. Voltage across the battery dipped to 7.7V when the starter was turned on, but only dipped to 10V when I was jumping it. Got a new battery, and now it turns over twice as fast as it used to, and catches right away. I guess the battery must have been going bad slow enough that I never noticed that the starter motor was turning it over too slowly... I must have gotten used to it.

So, it would seem from my anecdotal results that a C42 MIGHT be triggered by a weak battery. Guess that's a reminder to not trust error codes from a voltage-starved computer. We'll see when I drive it the next few weeks. I'm just glad to be back in the saddle again!

 

[greywolf]

Sure. A C42 is displayed if the voltage to the computer is wrong. The anti theft resistor is there to reduce the voltage the computer reads so hot wiring won't work. The other side of the matter is if the voltage reading is too low.

 

[marshallnoise]

Sure. A C42 is displayed if the voltage to the computer is wrong. The anti theft resistor is there to reduce the voltage the computer reads so hot wiring won't work. The other side of the matter is if the voltage reading is too low.

I notice that this bike is very sensitive to weather. Especially with the lock cylinder. My friend with a GSXR1000 verified this was a Suzuki thing. My Yammies never had an issue with weather like this bike does.

But, some CRC Silicone lubricant down the lock cylinder cleans things up and makes the C42 go away on my bike. But one ride in the rain, I have issues again. :thumbup: