2007 LX470 p0335 crankshaft position sensor code

[jtwoods4]

2007 LX470.
Hey guys I've been trying to troubleshoot a very difficult problem and I can't resolve it. The other day I got a check engine light and traction control light pop on and I hooked up techstream and got the error code p0335 which is for a crankshaft position sensor. Keep in mind the truck is running fine and there are no misfires or any symptoms.
I ran over to Toyota and grabbed a brand new crankshaft position sensor and installed it. I've been cleared the codes and took the truck out for a drive and the code came right back with a check engine light.
So I removed the glove box and unplug the connector to the ECM where the crankshaft position sensor signal comes in. Turns out it's plug E6 and pins 20 and 21. I tested the resistance at that pinpoint on the plug and it read 1300 ohms. I tested the pins on the crankshaft position sensor and they tested 2300 ohms which is exactly in spec. I'm guessing at the ECM plug at read 1300 ohms because of the long wires running all the way to the sensor. Also the fact that I got a reading at the ECU plug tells me that the wires are not broken.
What in the world could be the problem? Truck is running fine with no symptoms but I can't clear this code and the check engine light keeps coming back on if I do clear it.
Here's a picture from the manual and a picture of my plug. Am I testing the wrong test points? The manual clearly says it is plug E6 and pin 20 and 21. Or is there something else that can be throwing this code? Also timing belt was changed 2000 miles ago and everything has been fine until today.

 

[AARONTLC]

I am a little confused. You said that the Crankshaft Position Sensor itself was 2300 ohms which is perfect, then measuring the Crankshaft Position Sensor from the ECM it measured 1300 ohms? This does not make sense to me. Am I not understanding?

 

[jtwoods4]

I am a little confused. You said that the Crankshaft Position Sensor itself was 2300 ohms which is perfect, then measuring the Crankshaft Position Sensor from the ECM it measured 1300 ohms? This does not make sense to me. Am I not understanding?

Yes that's correct and I just learned that at the ECU plug it should be roughly the same as the sensor I was just assuming it was lower at the ECU because of the wires running all the way up to the plug. So it sounds like I have something wrong with the wire.

 

[AARONTLC]

Yes that's correct and I just learned that at the ECU plug it should be roughly the same as the sensor I was just assuming it was lower at the ECU because of the wires running all the way up to the plug. So it sounds like I have something wrong with the wire.

So with the CPS attached your ohms went down by 1000. Strange. Sounds like you have a slight short. What I would do is disconnect the CPS and read those 2 wires. Should be complete open “OL”. If you get an ohms reading other than that, either there is a short or there is something else in the circuit in parallel.

 

[jtwoods4]

So with the CPS attached your ohms went down by 1000. Strange. Sounds like you have a slight short. What I would do is disconnect the CPS and read those 2 wires. Should be complete open “OL”. If you get an ohms reading other than that, either there is a short or there is something else in the circuit in parallel.

So you mean disconnect the plug from the CPS and put my tester probes directly into that plug and read the ohms resistance?

 

[AARONTLC]

So I have an 2001LC and I am looking at the CPS and it is a simple 2 wire circuit with no junctions or splices. If you disconnect both ends of the harness (disconnect CPS, disconnect at ECM) and you are indeed on the correct wires it should read open. Any other reading and you are shorted.

 

[AARONTLC]

So you mean disconnect the plug from the CPS and put my tester probes directly into that plug and read the ohms resistance?

Yes, with both ends disconnected so you are not reading into the ECM.

 

[jtwoods4]

Yes, with both ends disconnected so you are not reading into the ECM.

Okay guys I have an update It turns out when I was doing the original test at the ECU plug on pin 20 and 21 I was actually testing the wrong pins. This morning I moved over to the correct pins which are 20 and 21 I was just on the wrong side of the plug. I'm getting a perfect resistance measurement for the crankshaft position sensor. The pins I am testing are for the two wires that run directly to the crankshaft position sensor. I'm reading just above 2000 ohms on a cold engine and that is exactly right in the middle of the measurements range specified in the factory service manual. So this means I do not have a break in the wire. And I have installed a new crankshaft position sensor even though the old one tested good when I took it out. What in the world could be throwing this p0335 code if there's no break in the wire and I have confirmed that my sensor is good.
Here's the logic I am leaning to. The p0335 code is a one occurrence and it throws the code. Meaning if there is one error that happens that code throws. I am guessing that there may be a tooth on the crank reluctor plate that maybe dirty or something like that and it's causing one single faulty reading when the engine turns over a revolution. This one faulty reading is enough to throw a code but not enough to cause any symptoms as far as engine performance or drivability.
Does anyone else have a theory that they could throw out there?

 

[AARONTLC]

So, it is possible you have an intermittent issue. The most common issues with CPS’s are self induced. Usually the culprit is the wiring harness that feeds down behind the fan bracket has been routed incorrectly and the wires get skinned by the timing belt or fan belt causing bare copper to touch or gets cut open. Since you know which pins are correct, I would hook up my meter and inspect and try and move the harness that goes down through the front of the engine watching your meter for change. This is obviously easier said than done. I would say that you are moving toward having to reveal the front of the engine similar to a TB replacement. If the wiring harness is solid then you need to inspect reluctor behind the harmonic balancer. If you remove the CPS, can you look up in there and see the teeth of the reluctor wheel? Maybe do this first?

 

[jtwoods4]

So, it is possible you have an intermittent issue. The most common issues with CPS’s are self induced. Usually the culprit is the wiring harness that feeds down behind the fan bracket has been routed incorrectly and the wires get skinned by the timing belt or fan belt causing bare copper to touch or gets cut open. Since you know which pins are correct, I would hook up my meter and inspect and try and move the harness that goes down through the front of the engine watching your meter for change. This is obviously easier said than done. I would say that you are moving toward having to reveal the front of the engine similar to a TB replacement. If the wiring harness is solid then you need to inspect reluctor behind the harmonic balancer. If you remove the CPS, can you look up in there and see the teeth of the reluctor wheel? Maybe do this first?

Yep my step was to inspect The reluctor wheel next. I like your idea of looking up through the whole by removing the crankshaft position sensor. Maybe I can just rotate the engine by hand and look for any damage for missing teeth.

 

[Jack90210]

I love a good mystery! Keep us posted.

 

[jtwoods4]

I love a good mystery! Keep us posted.

Guys after testing the crankshaft position sensor circuit all of the wires the sensor etc I decided to take it up to a local shop that works on European and Japanese cars. Despite the code being p0335 indicating an issue with the crankshaft position sensor, The tech discovered that the camshaft sensor wire was stretched tight and rubbing up against a hot coolant line. He thinks the heat from the coolant line was causing it to malfunction in the computer didn't know what to do so it threw a p0335 code. He fixed the wire running to the camshaft sensor and everything is working great now no check engine light. Even though the timing belt was done 2000 miles ago and there were no issues, It turns out the camshaft sensor wire was not routed correctly and the issued just popped up 2000 miles later. Mystery solved. Hopefully this can help someone.