Topic: tacoma auto hub question.

[raybie]

buddy of mine has a 3.4 taco with a 5spd.  it wont go into 4wheel drive.  started checking things and have a question about the t-case switch.  two leads going into the switch on the t-case, one shows ground, the other shows 12+ volts.  if i test the lead that reads 12+ volts with a cheapy test light it will trips the vacum switch and lock the hub, however if i test it with a test light that is circuit protected that lead reads 12+ volts no matter what gear the t-case is in. 

it seems to be that the switch should triggers ground for the hub to lock and that the switch is not working right.

any thoughts, advise?

[raybie [OP]]

chirs, mike, someone??

i found chris's write up http://www.off-road.com/toyota/tech/add/index.htm 

When the transfer case gear shift is shifted into 4WD, the ADD system is actuated by the operation of the ADD solenoids located under the hood on the passenger side wheelwell. The solenoids are supplied voltage from the ADD relay which depending on the type of transmission the vehicle is equipped with, has it's ground completed by both a Transfer Position Switch and a Transfer Pressure Switch (V6 with automatic transmissions), or a Transfer Indicator Switch (4cyl.-- manual trans.). These solenoids control the vacuum signals to the ADD actuator which is mounted on the front axle. This actuator engages a sleeve inside the differential via an "intermediate shaft" which is attached to the driver's-side side gear shaft and clutch mechanism. 

 

so if i follow this right that switch send a ground signal when in 4wheel drive.  so the swith is bad.

[toyotaboy]

Dear Ray,

             I understand you need a tacoma airbox, call me.

                       James