Got my bike out for the warm weather and ran into a problem. Starter is cranking fine but I am getting no spark. Looked at my fault codes and got P0335 crank position sensor circuit error. I have done mods to the bike since it ran last season, but going over every detail of them leaves me at a loss for how they could relate to this problem. If someone could let me know the correct series of diagnostic tests that would be great. The bike is a 2013 scrambler. Thanks
Assuming that the work you've done hasn't damaged or left some component disconnected, check out the resistance of the CPS. On a late bike like that you should have the Triumph part number T1296505 sensor which should read around 210 Ohms.
These sensors were fitted after engine number 437493.
Before that engine number they fitted part number T1290131 which reads between 504 and 616 Ohms.
Follow the smallest loom that comes out of the triangular engine cover until you find the connector (it's on top of the airbox in most Bonnies, don't know about the Scrambler), disconnect it and measure its resistance.
The 210 Ohm figure comes from a member that first discovered the factory had changed the specs for the pick-up coil. We don't yet know the exact figure as it's not quoted in the service manual but 175 sounds about right.
Tell me you're joking when you say the oil pressure switch has been replaced by an M10 bolt. That switch doubles as a banjo bolt and without it the engine top-end will be deprived of lubrication:
Remove right hand cover check air gap clearance, remove crank position sensor and do boiling test. If problem persists then order new crank position sensor.
My main concern is since I am getting the specific fault code for my crank position sensor, is it safe to say I can only focus on that or would anything else other than that cause the fault code like coils?
Before removing the CPS for checks I'd ensure the wiring is sound, both from the sensor to the under-seat connector and then from there to the ECU pins A1 and A9 on the black connector.
Using the ohmeter or continuity tester check the cables for continuity to the ECU connector, disconnect it and see that there's no corrosion on those pins mentioned (see photo below), then with the connector unplugged see that there's no connection to ground from both the wires. They could be trapped or snagged on a sharp edge and shorted to ground somewhere.
I am not sure I am doing this right, so here are some photos of the tests I did. Is my meter at the correct ohm range? When I touch the two meter probes together they don't go to zero they stay at 1, which should change to 0 correct? When I switch the meter one click to the left and touch them together they slowly go to zero, but my meter manual says this mode is for diode testing. I truly am sorry for my inexperience in electrical diagnosing, I am trying to wrap my head around it the best I can.
continuity from female connector to ecu with ecu plugged in
No, I meant checking the continuity of the wiring from the intermediate CPS connector to the ECU.
A quick way would be to disconnect the ECU connector, locate the two pins that connect to A1 and A9 (Blue/purple and Blue/black), bridge or short them together with a bit of wire that'll fit inside the connector terminals and then with the meter at the range you have it on measure just as in the first photo. This will check both CPS to ECU wire runs at the same time, should read 0 or very low resistance.
That will check that the two wires are sound. Then using one probe on any of the 3 points: temporary wire bridge at ECU connector, or one of the two intermediate CPS connector put the other probe on a good ground or battery negative.
Both readings should show 0 Ohms or a very low resistance, like 0.2 Ohms. That last test will show if there's a short to ground somewhere between the CPS and ECU wires.
Looks as if the protective fuse is blown caused by some mistake in usage or trying to read Ohms in a circuit under power.
You'll have to remove the back of the meter to see it, It'll be something like a small (5 x 20mm) cartridge-type fuse of a low value, around 0.3-0.4 amps. Not easy to find such a low value fuse in local shops, but until you do you can use a higher value one of the same 5x20 size, but the meter protection will be compromised.
Here's a suitable 0.315A fuse from Radio Shack, part number 270-1046:
Fuses came in early. Checked to make sure my multimeter was working correctly before I tested again and it was. Meter stays at 1 while both probes are in female cps connector with ecu pins bridged and one probe in female cps connector, other probe on battery ground, and ecu pins bridged. I also inserted pins into the wire right after the female cps connector and tested to make sure there wasn't a loose connection. Didn't bother to measure while starting because of the failed female cps to ecu test. Next step would be to trace cps wires from female connector and try to locate an issue?
Is there any possible way replacing my R/R and grounding the wire that went to my neutral safety switch could cause this? I am confused how the bike ran when parked over the winter and then this problem arose.
Meter stays at 1 while both probes are in female cps connector with ecu pins bridged and one probe in female cps connector, other probe on battery ground, and ecu pins bridged.
Is there any possible way replacing my R/R and grounding the wire that went to my neutral safety switch could cause this? I am confused how the bike ran when parked over the winter and then this problem arose.
The "1" display means an open circuit. Check the meter is Ok by shorting the probes together in the ohms range. Should read "0" or very close. If you're really getting "1" then there's a break in the wire somewhere between the CPS and the ECU connectors.
Don't think grounding the neutral switch would cause it, although it means the neutral light will be permanently on.
I checked the meter multiple times by putting the probes together and on each end of a piece of wire. I did the cps to ecu test multiple times making sure all my contact points were sound and just couldn't get continuity.
Here is where I am at now. Unfastened the air box so I could get a little more clearance to work with. I unwrapped the two looms that go to the ecm connectors. The plug to the right of the ecm loom is the cps plug. The ground wire to the right of the cps plug is from the neutral safety switch, which gets grounded right next to my gas tank screws. I discovered this ground wire is attached to a plug in the same under frame area as the cps plug, which makes sense if you replace the switch you just unplug it from there. I looked at the wiring diagram in my service manual and the ground for that switch never comes in contact with anything else. On the loom for connector A, the blue/black and blue/purple wires seem to be not wound in with the rest of the wires, sort of laying on top which makes it easy for me. The one thing I can't figure out is how to trace from the cps female plug back to the ecm. Do the wires go directly from that plug to the loom of ecu wires shown or do they go up into another main wiring bundle and come back? The two directions the main wiring bundles go are back up the top tube of the frame, and down towards the engine along the front of the airbox.
One more thing, The connection I am bridging on the ecm should be the pins on the male side as shown in my photos correct? Wouldn't the current being measured be going to the female A ecm plug as the wires end there? Does the bridged current run through the B ecm plug and then back into the male pins of the A ecm plug as I am measuring it currently?
No, once the connector "A" is unplugged from the ECU you short the female terminals on the loom connector. That's just to check the wire loom from the CPS is sound.
Do the same test between the other cable run and ground, that's the one coming directly from the CPS. There should not be any continuity to ground there either. If there is, it might mean the loom is trapped or badly fitted inside the triangular cover and shorting to the engine casings.
Note in this photo of the newer type of CPS how the cable loom rides over sharp edges that can cut through the outer protection sleeve, circled yellow:
If both cable runs show continuity, no connection to ground, the ECU pins have no corrosion and the CPS seems to check out for resistance, everything seems OK.
There's just that 175 Ohm reading, would be nice is someone else reported what reading they've got from the newer type of sensor, that's part number T1296505, as fitted to engines beyond number 437493 .
The only figures I have are 210 Ohms reported by Philontheroad, and 205 Ohms reported by Tornado99 on this post, so if your meter is correct, perhaps 175 Ohms is a bit low, although, as I've said before wound components have a wide tolerance, ±10-15% is common:
Couldn't get any continuity with my meter in the 200 range. Kept going higher until I got to 200k. Then it showed 200. Tried again and couldn't get continuity with my meter at the 200k range. Switched it to 20m range and got .20. Couldn't get a photo with the meter displaying 200 at the 200k range because it wouldn't do it again.
I checked for a connection to ground with my meter at every single range and it read 1 at all times. I also made sure that my meter was working by touching my probes together before every check and reading 0.
While I had the time I figured I would check the air gap. It is perfectly 8mm.
Couldn't get any continuity with my meter in the 200 range. Kept going higher until I got to 200k. Then it showed 200. Tried again and couldn't get continuity with my meter at the 200k range. Switched it to 20m range and got .20. Couldn't get a photo with the meter displaying 200 at the 200k range because it wouldn't do it again.
In this test, are pins A1 and A9 shorted at the ECU wire loom female connector? if so you should get 0 or close to 0 Ohms with the meter set to the 200 Ohm range.
The white connector goes directly to the cps and the black female connector goes to the ecu. I have continuity from the black female connector to the ecu, but no resistance from the white male connector the the cps. I just realized the 175 I quoted earlier was when my meter was at the 200k range.
Could it be because it's for engines under #447045? Since my cps wasn't showing a proper resistance I ordered a new one. Parts from Triumph take longer than usual so that's all I have so far. My estimate is I will install the new cps on May 17th and post results. Thanks everyone so far!
Well I have a brand new CPS that I ordered from Hermys and when I measure continuity, it reads "open" as well. I'm waitin on my new ignition coil to come in to see if it starts. But I am still perplexed because the old CPS reads "open" as well.
Just installed the new CPS and cleared the fault codes. The error did not reappear. From there I buttoned everything up and routed the CPS wire. Bike started right up. Thanks for your help everybody! The knowledge and support from this great community never ceases to amaze me.
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