Hello guys,

My mom has a 1988 Ford F-150. From what I have read the problem is either linked to the ignition switch or park safety switch.
When you turn the key you get nothing. You have power to lights, dome light, etc. But, there is no clicking or anything. The 1st mechanic we carried it to replaced the ignition switch. It worked for about a two weeks with just using it a few times. The 2nd mechanic we carried it to also replaced the ignition switch, but thought it might be the park safety switch cause he could cross terminals on the (I think it is the starter regulator located on passenger side finder by battery) and it would crank, thus bypassing Park safety switch. We got it back and once again after about a month it does the same thing again.
What I am looking for is a testing diagram for the ignition switch, what is powered when key is in start position, run position and off position, so I can rule out that component, or not.
I will bypass the park safety switch, when I find it, I know it is on the driver side of tranny. What color wire(s) should I be looking for?
I have read tons of post on here that has pointed me in the right direction.
Also, the engine is not the original engine. It was replaced with a v8 from about an 03' Expedition.
Thanks for all your help

Mike

 

usually if you have a bad park switch you can hold the key on crank and move the shifter around it will crank. The lock cyl on mine went bad and acted the same as what you describe, its a cheap and easy part to replace

 

Sorry it is a 86' not a 88'. Anyway, I have done a continuity test on 2 of the ignition switches (one that another mechanic replaced and the one that I just took out of the truck) and here are the results. Don't think it is the switch.

A1 A1 I2 I2 S1
P1
Batt Batt A2 A2 P2


Key in Acc(turned back) - Continuity between Batt and A1,A1

Key Off - Nothing(what it should be)

Key ON - Continuity between Batt and A1,A1,I1,A2,A2

Key in START position- Continuity between Batt and I2, S1
- Continuity between P1 and P2

both switches pin out the same.

Edit notes: pinout is not exact but P1 is to right and between S1 and P2.

Thanks for any help

 

Upon farther investigation, I saw on the wires from the Neutral Safety Switch that 2 of the wires had been stripped. I hooked these together to bypass the switch and it tried to crank right up. I will replace the NSS instead of bypassing it.
Now it appears that it is not getting fuel.
Have to troubleshoot that now.

Thanks again

Mike