Land Cruiser 3.0TD No Start, Cam/Crank sensor

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kukushka
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Land Cruiser 3.0TD No Start, Cam/Crank sensor

Post by kukushka »

Greetings all,

I would like to ask for you assistance. I have been thinking about getting a Picoscope for automotive use, and to see what I could do with a scope, loaned a 2205MSO for this measurement.

The problem is a Land Cruiser J80 3.0TD with the 1KZ-TE diesel engine. The front diff was toasted and heat up so it destroyed some of the wiring. After the owner had fixed them, he could not no longer start the engine.

I think it is faster to look at these pictures, rather than for me to write the set-up, as both the electronics and the correct waveforms is presented, and the pin-out.

http://daemon4x4.org/tech/hiluxsurf/inf ... 0103im.jpg
http://daemon4x4.org/tech/hiluxsurf/inf ... 0104im.jpg

Using the scope, I followed Pico's instructions and used the battery - as the reference, but the manual instructs to measure between the sensor + and - terminals at the ECU.

If the TDC sensor at the crank is connected, the engine will not start. If disconnected, starts right away. So it can run with only the NE signal from the camshaft. The wiring to both sensors are OK.

Here is a link to the psdata. files, I could not attach multiple to the forum.

https://onedrive.live.com/?id=631F7464A ... 464A0F91D2

And the explanations,
CRANK_UNPLUGGED_BAT- (from the crank sensor with wires unplugged, waveform like the reference)
CRANK_CONNECTED_BAT- (from the crank sensor with wire plugged, waveform looks now like the camshaft reference)
ECU_PIN4__BAT-_CAM_Idle (from the ECU CAM sensor + - BAT -, engine running, looks bad)
ECU_PIN5_BAT-_CAM_CRANKING (from the ECU Crank sensor + - BAT -, engine cranking, looks like camshaft reference)
ECU-PIN5_BAT-_CRANK_IDLE ( from the ECU Crank sensor + - BAT -, engine idling, looks like camshaft reference)
ECU_PIN17_BAT-_CAM_Idle ( from the ECU Cam sensor - BAT -, engine idling, this should be in the sensor +)
ECU_PIN18-BAT-_CRANK_Idle (from the ECU Crank sensor - BAT -, engine idling, both cam/crank look the same)

Any ideas?

kukushka
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Re: Land Cruiser 3.0TD No Start, Cam/Crank sensor

Post by kukushka »

Hello,

OK, I got it figured out. The VR-sensors can not be measured agains BAT -, or they can, but the correct waveform is displayed when the negative wire is probed at the ECU with the positive probe of the scope.

Here is a capture with tho channels, red is the NE-sensor and Blue te TDC-Crank sensor. Measured at the ECU with positive probes on the VR-sensor positive pins and negative probes at the vr sensor negative pins.

It is clear to see that the timing has jumped. This was also the reason the engine would run without the TDC signal. Once it got it, it misses the pump injection timing. The timing has propably jumped when the front diff was locked up and destroyed.
Attachments
PIN4-5_17-18.psdata
(586.24 KiB) Downloaded 784 times

victor2k
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Re: Land Cruiser 3.0TD No Start, Cam/Crank sensor

Post by victor2k »

Hello,
Indeed the timing isn't like in RM.
Here you will find a pdf with TDC vs NE signals.
But why the timing gears has slipped(between crankshaft and injection pump is used timing gears.check the thrust clearance and wear of idler gear.I saw a KD engine what ended badly because of timing gears lubrication issues)?
Maybe you must check this on your engine.If you will need a pdf RM just tell me.
Regards
Last edited by victor2k on Wed Jun 13, 2018 8:30 am, edited 1 time in total.

kukushka
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Re: Land Cruiser 3.0TD No Start, Cam/Crank sensor

Post by kukushka »

Hello again,

The same problem persist. Engine won't start with normal cranking. Will start every time with a start-up spray (sorry, I know)

The injection pump was changed and the timing checked. But still the cam/crank synchronization is at the same spot, but the once the engine is running it runs fine. If the timing was off like in the picture, it would be close to 60 degrees, so the engine would not run.

The car once running generates a fault code 14, timing control valve. Here is a ¤"##% scope trace, two with the engine running OK and one where it runs poorly. Could this mean a problem with the coil or the transistor driving it?

Normal traces,

https://onedrive.live.com/
cid=0631F7464A0F91D2&id=631F7464A0F91D2%211647&parId=631F7464A0F91D2%21104&o=OneUp

https://onedrive.live.com/?cid=0631F746 ... 04&o=OneUp

Faulty? No voltage / current draw?

https://onedrive.live.com/?cid=0631F746 ... 04&o=OneUp

https://onedrive.live.com/?cid=0631F746 ... 04&o=OneUp

Thanks for your input.

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Re: Land Cruiser 3.0TD No Start, Cam/Crank sensor

Post by STC »

Kukushka.

First, I have not looked at all the attachments. God knows what I am clicking on. I don't have anti virus, don't want it, don't need it. Happy to look at any PSData files.

Moving on.
The VR-sensors can not be measured agains BAT -, or they can,
I have yet to come across anything on a car that cannot be measured against B- ?

Sometimes we measure a sensor with the ground to B- and we will see that the signal ground is "Floated" above 0v, possibly for circuit fault detection. Measuring across that sensor will give a great signal but the scope will assume whatever is on the black lead as 0v. This can be misleading - Devastation in the Automotive "First Time Fix" Diagnostic Arena.

The scope will show the Voltage on Blue Lead (Assuming Channel A) Minus whatever is on the Black Lead. Purely the Potential Difference between the 2 leads.

but the correct waveform is displayed when the negative wire is probed at the ECU with the positive probe of the scope.
If you are Probing the B- Wire at the ECU with the Positive Probe and the Negative Probe is in the Component Positive Wire you will see an inverted picture.

If you are Probing the B- Wire at the ECU with the Positive Probe and the Negative Probe is in the Component Negative Wire you are conducting a VOLT DROP test.

If you are Probing the B- Wire at the ECU with the Positive Probe and the Negative Probe is in the Component Negative Wire you are conducting a VOLT DROP test. It then follows that if you can see
that the correct waveform is displayed
You have uncovered High to Infinite Resistance in that Wire. You are Looking At "Volt Drop" not the "Signal" Yes they will be similar but possibly inverted.

Cut all the wires from VR to ECU - At Both Ends - Put your own new ones in and test again.

At this time of night, given my bad habits, I have got that very right or very wrong. Hopefully the former.

Hope that helps you.

kukushka
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Re: Land Cruiser 3.0TD No Start, Cam/Crank sensor

Post by kukushka »

Hello STC,

Can you specify why the Toyota's FSM tells to measure between the VR-sensor leads in AC-setting from the ECU-socket?

I am sure there are no viruses in .jpg files. If you could be so kind to look from my first post the second .jpg attachment that shows the correct waveform.

Then at my second post there is my capture in .psdata. Comparing that to the Toyota's specification shows the deviation.

If a measure the wires with an ohmmeter, the correct resistance is shown at the ECU terminals, not high to infinite. Same resistance from the sensor without wires and from the ECU end.

I read your reply over and over again, tried to see where I got it wrong. Can you check one more time, please.

Thanks, I am still a beginner so bare with me.

kukushka
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Re: Land Cruiser 3.0TD No Start, Cam/Crank sensor

Post by kukushka »

Also TiePie, an oscilloscope manufacturer tells to measure VR-sensors between the sensor leads.

tiepie-automotive.com/en/Measurement_examples/Sensors/Crankshaft_Sensor_Inductive

I am sorry to post examples what you guys might have done in real-life a million times, but I am a bit confused.

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STC
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Re: Land Cruiser 3.0TD No Start, Cam/Crank sensor

Post by STC »

Can you specify why the Toyota's FSM tells to measure between the VR-sensor leads in AC-setting from the ECU-socket?
Not with any certainty but I guess measuring it that way would fit with the Training and Tools they provide.
I am sure there are no viruses in .jpg files. If you could be so kind to look from my first post the second .jpg attachment that shows the correct waveform.
Then at my second post there is my capture in .psdata. Comparing that to the Toyota's specification shows the deviation.
I don't have , don't want, wont have anti virus. Please post PS Data and I will endeavour to assist to the best of my ability.
Also TiePie, an oscilloscope manufacturer tells to measure VR-sensors between the sensor leads.
There are no Definite Rights and Wrongs - Measure both ways for your own sanity - especially when presented with 2 options. Your eyes will not lie to you.
Thanks, I am still a beginner so bare with me.
Indeed we all were at some time. Nothing wrong with that. I love the fact that you have made the investment into a Picoscope and if I can I will assist and help. Maybe learn from you and the car you have.

It is a win win, or should be for all of us.

Good weekend :D :D

Liteace
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Re: Land Cruiser 3.0TD No Start, Cam/Crank sensor

Post by Liteace »

kukushka wrote: The problem is a Land Cruiser J80 3.0TD with the 1KZ-TE diesel engine. The front diff was toasted and heat up so it destroyed some of the wiring. After the owner had fixed them, he could not no longer start the engine.
Just a thought, looking at your
" PIN4-5_17-18.psdata"
double check the new wiring they done, make sure the wires are not reversed on the crank sensor, should be:

ecu pin...5 to pin 1 of crank sensor
ecu pin..18 to pin 2 of crank sensor

kukushka
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Re: Land Cruiser 3.0TD No Start, Cam/Crank sensor

Post by kukushka »

STC, Here is the .psdata attached.

Crank/Cam synchronization. Blue trace is the TDC sensor, red trace is the NE sensor that reads the position of the injection pump. According to Toyota, if I am not mistaken, the blue signal should be right between the missing tooth on red signal, not where it is now.

Liteace,

I have checked the wiring, and if it was the wrong way around, it would change the polarity captured in the trace blue trace in the file "PIN4-5_17-18.psdata". Now it is as spec, first up, then down.
Attachments
PIN4-5_17-18.psdata
(586.24 KiB) Downloaded 660 times

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