1988 2.9L neutral safety switch?

[35Remmy]

Either or?...im testing the master switch on the drivers side that has both the door locks and window switches.... So i should be finding ground wire and looking for that 0?

 

[RobbieD]

OK, try this out on the driver power window; basic testing 101.

Set your meter for DC VOLTS.
On the back of the driver window switch (where the wires go in) poke the meter red lead into the connector, touching light blue black wire's terminal (leave it here for now).
Ignition switch ON.
Now touch the meter black lead to bare metal (like a bolt head). Meter reads 12 volts = pass.
Take the meter black lead and touch:
Switch black wire terminal. Meter reads 12 volts = pass.
Switch yellow wire terminal. Meter reads 12 volts = pass.
Switch red wire terminal. Meter reads 12 volts = pass.
Now remove the meter red lead from the light blue/black, and poke into the connector to touch the red or yellow wire terminal (take your pick; these are the two wires going to the window motor).
Take the meter black lead and poke into remaining other wire terminal, red or yellow (i.e. the one not used in the previous step). Your meter is now connected between the two window motor wires.
Work the driver switch up, then down. The meter should show (as a pass condition) plus voltage one way, negative voltage the other direction (look for a "-" in front of the number).
>>> If you unplug the motor, the meter will show a full @ 12 volts; if the motor is plugged in, the voltage is usually less (but the motor will also be turning).

Any step failing, shows the problem area.

Hopefully these steps will make some sense to you- we've just tested power into the switch, tested ground into the switch, tested both motor grounds out of the switch, and then finally tested the switch operation in both working conditions.

Don't forget to turn ignition back off : )

 

[35Remmy]

Ron, i owe you at least a 30 pack for this information....

 

[35Remmy]

ROB

 

[RobbieD]

ROB

Haha! Thanks, man.

Seriously, basic electrical is not hard. Use your manual, work with it, take it slow and think about what's going on there, and you'll get good at it.

Good luck!

 

[35Remmy]

Ok Rob so 1st test passed....light blue wire is giving me 12V, but that is it. Nothing from the other 3. Yes, ignition switch is on.

 

[RobbieD]

That indicates that the black ground wire (57) is NOT grounded. That's the G101 ground I mentioned in post 19. G101 is also the power lock motor ground, so that could also explain why your doorlock relays will click, but the actuators aren't working.

Look at your EVTM. G101 is bolted to ground on the radiator support, and goes through one connector close by (C180); page 44, figure 2 show both of these. Find and check the G101 ground point- a black wire with a ring terminal that'll come out of the harness running along the top of the radiator support, driver side. C180, below the driver headlight, gives you a good place to pick up the black (57) wire, for testing continuity to ground.

 

[35Remmy]

Rob, im positive i have this grounded......look here....

 

[35Remmy]

Its to the right of the relays.....freshly grounded

 

[RobbieD]

Thanks for the pic. I see what you're saying, and that does look like G101. I'm assuming that the windows and locks are still not working, and that your testing still shows no ground on black (57) at the driver switch, right?

 

[RobbieD]

Next thing I would check is continuity to ground on the black (57) wire at connector C180 which was originally below the driver headlight (see drawing at 44-2). Meter on OHMS scale, find the black (57) wire on C180, and poke one meter lead (red or black doesn't matter) into the connector touching the black (57) terminal, and then touch the other lead to the bolt holding the black wire ring terminal; "0" = pass. [should this step fail, remove the lead from the bolt and try other ground points, like the engine block] Do this same test on BOTH sides of C180.

Provided that you've lost the ground wire at the driver switch, you're basically starting at its beginning point and testing your way back to the switch.

 

[35Remmy]

Ok, it checks out. From 1 to 0.4

 

[35Remmy]

Actually i take that back. If i test the switch side of the harness im getting a 1, no change

 

[35Remmy]

So, i was a little eager and took it upon myself to investigate further...and in doing so i accidentally broke the ground wire where it enters the door. So, i tested that ground on the door side and still no continuity....same results. Does that mean the problem is somewhere in that last 2 feet of wire since the ground on the feed side is checking out ok for continuity?

 

[RobbieD]

Can you access where you found the broke wire? If it does test good on side coming out of the fender, splice the broken wire back together then check for ground at the switch again. Two things here:

Back when I did this for a living, when troubleshooting inoperative power doorlock and window systems it was very common to find a broken wire in the harness between the door and vehicle cowl. Opening and closing the door flexes and stresses the harness, especially over many years. A lot of times the plastic insulation would be fine, but copper strands inside would be broken. As you "accidentally broke" the wire makes me think you had an issue here; wires just don't break that easy.

When you do splice the broken wire, don't put the splice where the harness flexes when the door is opened and closed. Add a short length of same-gauge wire and tape one splice well up into the fender / door jamb opening, and pull the second splice inside the door. You don't want the splice flexing- it'll fail later. Pass the new wire through the door grommet and tape the harness like is originally. Make the best splices you can; soldering's best, insulated crimp terminals are OK if done right, and even "strip and twist" can be OK if done right.