still trying to diagnose 4wd problem

[stukaneche]

Hi,

My KZN185 has been failing to engage 4wd for months - the light in the dash just keeps flashing. It has been into 4 garages and everyone just scratches there heeds. Tonight I got it to engage 4WD by swapping over the vacuum hoses (pink and blue) beside the throttle. I had to swap them over to disengage the 4wd but atleast it is working (sort of). When i press the button on the stick the vaccum does not appear to swap sides (pink and blue). Does anyone have any ideas?

[hiroler]

I would of thought you have a split hose on the side that is not working!!

[Justbrad]

I would of thought you have a split hose on the side that is not working!!

Sounds feasable

[stukaneche]

Hi, there is no damage to the hoses on the other side. I am thinking that whatever chages the vaccum from one VSV to the other VSV is not getting a signal to change. Am i getting warmer?

[TonyN]

sounds like one of the VSV's isn't working, check to see if you can hear it clicking when you press the button.

the vacuum should switch from one valve to other when you press the button

it will wait for the t/case to select first, so if you have a duff position switch on the t/case, the ECU will wait before switching the VSV's, so test for voltage on the wires to see if the VSV is getting power.

[steved]

Had the same problem on mine and it turned out to to be a broken earth return wire down on the front axle ADD switch it was a devil to find because it was broken just where it goes through a bracket that is hidden under the sump and when you disconnected the connector from the switch and tested it the broken earth wire contacted the bracket so it tested ok, If you disconnect the wire on the higher of the 2 connectors that is just about level with the sump flange and bridge the connections this will simulate the front ADD switch operation, and the allow the vac valves to switch over.