Autronic SM4 Error - Engine will only crank

[BlackSupra]

Engine is 7MGTE.

Error being recieved is:

Flash 3:3 Err crnk i/p missing
crank i/p fault detected
crank ip pulses missing

and

Sync/cyl 0%

Have rail fuel pressure and spark, so the issue lies with the Autronic.

I have shortened section of the loom, however nothing mechanical has been touched, so i need to assume the issue is in the wiring.

I beleive im running a hall sensor on the crank and a reluctor on the CPS

Can anyone shed some light as to which sensor is the issue and how to test to determine the issue? I have unplugged both the crank and the cam sensor and this has not affected the error code generated by the ECU (after clearing the error histroy).

Sensor ground is fine as other sensors are operating fine.

Anyone have any ideas?

[thechuckster]

are you sure you didn't swap the signal and earth return for the Crank sensor when you shortened the loom. OR swapped the earth returns for the two sensors?

Without knowing much about the Autronic, does 'pulses missing' mean it received no pulses, or that that it just missed some (e.g. expected 24 crank pulses for 1 cam pulse but got 1 instead).

Are you getting any RPM showing at the ECU? and does that match the likely crank speed (should be ~300rpm).

Do you get an error with the sensors unplugged and engine on but not yet cranked? Or after you try to start it? (if the later, then maybe your wiring work is fubar)

btw: does the Autronic software have some kind of trigger logger? I only ask as the Megatunix software for MSefi has a diagnosis tool for that - basically shows you the output of the A/D convertor as quickly as it can log it. Helpful if you are getting dropped trigger events or dodgy trigger inputs. Wondered if Autronic might have similar tool?

[The Witzl]

sounds like you mightve done something with the crank position signal.... and i would suggest that most likely is something to do with the wiring of it.

Time to crack out the old multimeter champ.

[JustCallMeOrlando]

I'm with Witzl...you need some multimeter love. Check back to the ECU, that everything is where it should be.

[CrUZida]

You've got about 8 days to get it done.

Reckon thats do able?

[BlackSupra]

Probably not, but I'll have a crack at it this weekend.

[BlackSupra]

Actually, how should i test for this?

The three wires:

8+ volts - easier enough
Ground - easy enough
+ive trigger - what range does it need to be in?

If the sensor is grounded and as 8V+ how do i test for operation?

[CrUZida]

+8 volts?
Is that an Autronic thing?

That aside, you'll need a CRO or at worst analogue multimeter.

[JP]

isn't the 8V feed usually used with nissan sensors etc?

Shouldn't need a power feed wtih toyota reluctor triggers.

[crownman]

Hello peoples I had troubles with a 1JZGTE that had fuel and spark but would not fire PROPERLY the wiring polarity for the crank angle sensor and cam angle sensor MUST be the same either one way or the other. regards crownman.

[CrUZida]

JP, AFAIK he's runninga hall effect sensor on the crank, hence the 3 wires.
I don't know the source of the sensor though.

[The Witzl]

i would be using a multimeter on "CONTINUITY" test... you know the buzzer..... and making sure that the correct wires at the crank sensor are properly connected thru to the correct pins on the ECU plug.

[BlackSupra]

So took the multimeter and tested away this is what i found:

Crank Sensor wiring

• WH-25 cyl Pulse (+ve)
• RD-11 8 volt supply
• BK-22 sensor ground
  
• All wires have continuity
• Ground is earthed at ECU and circuit through ecu
• 8 Volt supply is good

Cam (CPS) Sensor wiring

• W-26 sync (+ve)
• BK-41 sync (-ve)
  
• Both wires have continuity to ECU

I followed crownman's advice and swapped the wiring polarity on the Cam sensor and cranked it over. Without a laptop on hand i couldnt measure the error, however the engines behaviour has not changed at all, continues to crank over without roaring into life.

Any other ideas guys, this has me stumped and i just want to burn the car now.

[river]

Hi,

Call Dave at SAS. You're not getting anywhere at the moment and unless you want the car to immobile and rust away, you're going to have to bite the bullet and maybe spend a some coin to get someone like Dave to fix it up.

seeyuzz
river

[BlackSupra]

Yep tried calling Dave, he is away all of next week.