ln130 front diff problem lexus v8

[smiddy]

a mate of mine has just finished putting a lexus v8 in to a ln130 hilux that he has just brought about 4 days ago, but he had it in the beach the today an realised the 4wd isnt working. long story short, the gear stick goes in to gear easily, but dosnt seem to be electrically activating the 4wd solenoid, he reckons he cant hear a solenoid clicking. If you jack the front of the truck up and try it in 4wd, the front wheels dont turn at all. he thinks its alomst like the front brakes are jammed on preventing the wheels from turning. I havent had a look at it myself yet, although he reckns he checked the hubs and all the other basic things, any electronic wizz kids out there who have had this problem before?

[Jerry]

The surfs had an system called ADD I think (ie its not the vacuum solenoid system like the prado's/cruisers).

[Jerry]

Found it ....

http://www.toyotasurf.asn.au/techsite/add.htm

is there a vacuum pipe from the intake manifold on the 1UZFE to the air tank on the ADD System?, Check the fuses as well?

(from the link above)

Trouble Shooting
This is what I do to check my system and it may vary. I have a manual with the 4WD button on the transfer gear stick.
When it is in 2WD, I can twist the front drive shaft and when I jack up the front axle both wheels will turn freely by hand.
To change from 2WD to 4WD or back, vacuum is required so therefore the engine has to be turned on. The tank under the right wheel will allow me to switch back and forth about 2-3 times without replenishing the vacuum but the key needs to be in the ON ( or START) position When the 4WD button is pressed, I can feel the electric motor engage the transfer case. When the transfer case is engaged it sends a signal to engage the VSV. If the sensor is disconnected, the VSV’s will not click.

Checking the vacuum is just a matter of pulling of the hoses one at a time. I have easy access to the ADD valve on the front diff and can check that I have vacuum on the correct hose. If you have access to an Ohmmeter, the VSV’s have a resistance of about 40ohm and can be switched by manually applying 12volts. When the yoke on the ADD valve is moved into the 4WD position, it is then that the 4WD light will illuminate on the dash. When 4WD is engaged, the –ve signal used to illuminate the signal on the dash is also used to notify the ECU that things have changed.

If the electrics don’t work, and the VSV are not switching then check the 4WD fuse (20A) but if the VSV are switching and the vacuums are correct and the indicator light isn’t working then it is the GUAGE fuse (15A) but this would be evident that none of the other indicator lights aren’t working.

If you jack up the front of the car and 4WD is selected then the front drive shaft should turn at the same rate as the rear drive shaft (if the rear wheels are on the ground then you will not be able to turn the front drive shaft). And when you turn any front wheel, then either the front drive shaft or the other wheel should turn.