problems with FAV solenoid - no work, but getting very hot! ::fixed::

[softic]

ok, here are the answers:

1. test point 5 injector(+) +13.9V
2. test point 8 injector(-) +13.2V
3. test point 23 injector(+12) +13.9V
4. test point 1 FAV drive (check resistance. not voltage) 650-680 Ohm
5. test point 16 (IDC%) from 0.2V on idle up to 1.2V on load
6. test point 15 internal 5V reference 1 +4.97V
7. test point 11 internal reference 2 +9.07V
8. test point 30 internal reference 3 from +3.35V on idle to 7.66 on load (after the threshold is reached and FAV should be opened)

this all was on running engine with LED gauge switched on.
sorry, I forgot to take results on switched off engine, because when engine is OFF the LED is also OFF... will make new measurements 1.5 hours later.


the bottom of the mainboard:
http://aklepikov.ru/wp-content/uploa...0614-00021.jpg

the top of mainboard:
http://aklepikov.ru/wp-content/uploa...0614-00019.jpg

[Richard L]

There is enough information there for me at the moment, no need to make more measurements.

As far as the functions of the system, everything is perfect. The only exeption is the pin1(FAV) drive. there shoud not have a resistance of 650-680 ohm.

Is this test done on a blown transistor or a new one?

[softic]

Richard, the test was done on a blown transistor.
I can replace it with a new transistor, but I am 90% sure it will blow up even before I connect FAV solenoid (((

[Richard L]

I really cannot understand what is going on, everything tested normal.
Can you remove the blown transistor and do the same test #4?

Richard

[softic]

sure I can! should I just remove transistor, not replace with a new one?
I think that by removing the transistor this would imitate the 'closed transisto / FAV-off' situation.

[Richard L]

I like to see if the resistance is still there when the blown transistor is removed.

[softic]

Richard,

I have just checked test pin #1 (FAV control) after removing broken transistor and have following results:
- when power is OFF, but ignition key is ON, the impedance is 8.5 MOhm, which should be fine
- when the power is ON - the voltage on idle is 0.1 and on load / throttle up to 1.4V

Let me know, what are my next steps.
Maybe I can connect some external transistor based solenoid driver? I assume you use PWM, right?

Regards,
Alexey

[Richard L]

I have a question on pin 1 test: Is the FAV+ cable plugged into the controller during your test?

The strange part of this test is: pin1 should not see any voltage until the FAV is plugged in. When it is pin one should see 12V (battery voltage) all the time, regardless of idle of load.

We might have found something.

The next test:
(still without the transistor)

There are three pins for the transistor, can you check all three. The center pin is the same as test pin 1. Theone on the left is power ground (black molex wire). The one on the right is PWM drive signal. At idle it should read below 1V and over 5V at full load. This is donew with the RJ connectors facing away from you.

[softic]

Richard, the FAV harsess was disconnected at all tests.
Also I do not connect this harness to a FAV solenoid to reduce any extra load on the system

What is our next test?

[Richard L]

The strange part of this test is the ~12V signal on pin 1. It should not be there when the FAV is not plugged in. It is especially strange it changes between idle and loaded.

Can you rememer if there is any sudden change conincide with system problem. Other than the engine rework. Are any of the wires been disturbed.

The next step would probably be unplugging all the RJ connectors (including the gauge), just leaving the grey harness plugged in.

I would like to concentrate in the test point 1 with only grey harness plugged in. Then retest pin 1 as follows:

1. Just the molex
2. Just the pump harness (blue)
3. Just the FAV sensor harness (yellow)
4. Lastly the gauge.

I like to know where this strange 12V comes from. If the 12V is present before with only the grey harness plugged in, we have found the culprite.