If you are measuring to one side of the fuse holder, you are not testing to ground.

The fuse holder for the parking lamps, 1 side is to the main headlamp switch, the other side is to the parking lamp circuit on the truck. No ground involved with the fuse holders.

 

how do i test to ground

 

USe your meter to test the continuity from the brown wire to ground with the switch turned on.

 

no signal from brown wire to ground with switch turned on

 

Are you sure you have a good ground ?

You said the switch tested good, and the parking lamp circuit is not a short to ground. This means it should work, considering the main headlamp switch blows the fuse ( powering the whole switch ) the moment you switch to the park lamp position.

Was this with both switch connectors plugged in ( thinking instrument illumination issue.

 

I just rechecked everything again making sure i had a good ground, nothing from brown wire to ground, even without the head lamp connector plugged in with switch both on and off. there is a third plug for the dimmer and the dome light. also rechecked from brown wire to inside pole on fuse #7 which does have a signal.

 

according to the manual the main light switch and park lamp relay are on the same fuse

 

What manual are you looking at ?

1997 Owners manual, page 140 Fuse 7 Parking and tail lamps. No mention of main headlamps or the parking lamp relay.

You do not have a parking lamp relay, due to no Autolamps installed.

Did you have the instrument illumination connector in when you tested ?

Maybe try unplugging the instrument illumination connector, and see if the fuse blows. Don't know how it would, you tested from the input to it with the brown wire to ground, so that should not be the case, but best to test it.

 

98 manual page 140, 97 does not have the multi function switch, correct? i could be wrong, maybe i am looking at the wrong manual.

 

still blows fuse with instrument illumination unplugged

 

OK, good to know which model year you have, the thread has 2 MY listed for some reason.

The 97 does have a MultifFunction switch

If the instrument illumination unplugged still causes the problem, then the problem is with the switch or the wiring.

 

the switch has some diodes and resistors on it, looks to be many things that could go wrong with that, and im not a professional, but the testing ive done tells me its good. could it test ok and still be bad

 

I am just going from the obvious.

The fuse blows when you turn on the parking lamps.

The parking lamp circuit does not have a short to ground, and the instrument illumination circuit has been isolated from the test. You also said the switch tested good.

With your test results, there should not be a problem.

Is the fuse the correct size of 15A ( not a smaller one installed ) ?

 

the 98 manual would say the problem is the switch (no relay), the 97 would say its parking lamp/tail lights and it is a 98

 

yes, the fuse is 15a