So ive been having issues with my pcm resetting itself every time I turn off the truck . Now with it doing this I cannot get my truck smog, because I have to redo the drive cycles every time. I checked all the fuses and relay and they all seem good. Now I keep getting these codes P1000 which is the drive cycle one , P1116 ECT sensor out of self test range, P1127 Exhaust temperature out of range, 02 Sensor Tests Not Complete. I also put in a new battery and alternator not to long ago so I know thats good. I just cannot for the life of me figure this out

 

Have you followed the complete and
proper "Ford Motor Company Driving Cycle" ?

Ford Motor Company Driving Cycle

 

Yeah I have but when I turn off the truck it restarts it. Thats my problem

 

2000 Ranger, check fuse #6 in engine fuse box, 10amp, that should have 12v all the time its for PCM Memory

Don't just "look at a fuse", test it or replace it

 

Ill check it now

 

So both the old fuse and new the fuse both say they're at 12 volts .

 

Then its either one of three things

Fuse #6 is losing power when starting, bad connection in fuse box or at power distribution point, test voltage at #6 while cranking engine over, should drop no lower than 9.5volts

OR

#6 fuse wire at the PCM is bad, you will need to pull the PCM connector off, disconnect battery first, pin layout seen here: https://www.explorerforum.com/forums...cm1-jpg.34210/

Pin 55 is a Yellow wire, from fuse #6, should have 12v when battery is reconnected, check connector and PCM, there can be water intrusion if hood gasket leaks

OR

PCM is bad, not getting 12volts internally to hold memory

 

Thank you ill check it out and get back to you!
Thank you so much for the help!

 

So that diagram is for the SOHC mine is the OHV which I forgot to add, But the pin 51 is a yellow wire and there is no power or anything running through it.
Also fuse #6 is dropping down to only 11.50 when I crank the engine

 

Pin/hole #55 not 51

Its the same on all 1995 and up Ford PCMs, so engine(even year) doesn't matter, yes yellow wire in 2000, Ford changed to Black/light green wire in 2002, but still pin/hole #55

If the yellow wire in #55 doesn't have 12volts when battery is connected and fuse is in place then you found the problem, that wire is broken somewhere
You will need to find the Yellow wire coming out of the fuse box and test it, I use a sewing needle to pierce wires to test for voltage or OHMs

Then run a new jumper wire from Fuse #6 to PCM connector #55 yellow wire

Wire could be broken under the fuse itself

For temp fix you can use a fuse tap, google: fuse tap images

Many "flavors" of these, but it would allow you to keep the 10amp protection and run the 12volt full time power to PCM so you can get emissions tested once drive cycles are complete
Then you can tear things apart more to find the broken wiring

I don't see any other solid Yellow wires used on the PCM connector in 2000 so that should be the wire you need to splice into

 

So traced the problem to where the fuse box connects the engine harness and it wasnt getting any power there so I spliced in a wire to get me by for now.

 

One more problem and im done my O2 sensor is stuck at 99.2% with zero voltage im guessing its bad and needs to be replaced or possible to clean it?

 

Good work on the wire

You can't really clean O2 sensor, they use a chemical reaction inside to detect oxygen levels, and they run out of that chemical after 100,000 miles or so

But this is the O2 senor after the Cat converter, B1-S2, downstream O2 sensor so should last 200,000 miles

You can try a new one for sure, I would have a close look at the wiring on the connector, and the harness near exhaust system, common to get a melted wire

There are 4 wires on every O2 sensor, 12volt and Ground wires for Heater in the sensor
Then 2 wires for the sensor itself

O2 Sensor generates its own voltage once it is heated up above 650degF, .1 to .9volts, so not much, .1 is high oxygen, .9 low oxygen
So O2s don't work until engine and exhaust warm up
Downstream O2 should run .7-.8 volts all the time, because Cat converter should be burning up most of the oxygen

 

Yeah that was a pain in the *** to trace so I guess down the road ill replace the wiring harness for the engine. Thank you for your help! No way I would of solved this on my own.

Funny thing I replaced the 02 sensor already. I thought bank 1 sensor 2 was the one by the headers. So well damn, I guess ill check the wires tomorrow on it.

So wtf is this plug? Its pretty torn up on the inside and all that