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No crank no start no communication with scanner


Aldo0280

Member
Joined
Mar 30, 2019
Messages
9
City
Northern California
Vehicle Year
98
Transmission
Automatic
I am trying to help a buddy with a 2006 ranger automatic, 3.0, 2wd, that wont crank, & has no communication with my scan tool. He has replaced the ignition switch & the starter & still no luck. The obd port has power, all fuses ive checked were good. Cel comes on with key on, & theft light comes on for a sec then goes off? He has the ignition switch out & we have just been turning the key to the start position & then moving the bar on the ignition switch. Does the switch need to actually be installed to work or can i just continue to move the lil rod by hand? Also does anyone have some wiring diagrams for the ignition switch & pcm pinouts? Any help would be very much appreciated!
 
Ignition switch wiring. One of the diagrams has the switch and then letters that you follow to other destinations in the wiring. I tried to get the diagrams with those lettering destinations also.
 

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Engine Control Module
 

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Man your awesome thank u! Any idea's on what wires i should be checking? I did some more testing last nite & i can get the starter to crank by jumping the relay but truck still wont start. Also the starter relay has power on one pin with key off, power on the opposite side pin with key on & also has ground? Also pcm relay clicks when key is turned on & theft light goes on for a sec & then off?
 
One of them is the connector + description and the other is descriptions.
 

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Hey thank u very much for the help! On the pcm pinout do i look at it from the wire/harness side or the pin side to locate the correct pins? I was working on an altima a couple weeks ago & i spent half the day fixing the wrong wires cuz the pinout diagram is supposed to be read from the back side of the harness?
 
Been there done that with a Honda. The only way I know to get yourself oriented is to look at the PCM diagrams and find some circuits and see what color they are. Write the color and description down, then look at the PCM pinout list for the same circuits, what pins they are, and find the same color wires.

I usually look at the pinout and find a circuit in the corner somewhere. Then go to the diagrams and figure out the color of the wire or wires, and then go back to the actual plug and see what corner it's in.
 
Ive tried my snap on solus ultra & ive tried forscan & neither one work i figured if those 2 didnt work nothing would but yes i have a couple other scanners i can try. I purchased the alldatadiy so i could follow the diagnostic flow chart for no crank. But i keep getting stuck where it says to test the resistance on the wire from the pcm to the starter relay. It says if the resistance is more than 5ohms to repair the circuit & check for normal operation. The resistance was more than 5ohms so i ended up running a whole new wire but i still have no crank no communication. I really think its gotta be the pcm itself. Its actually a buddys truck & im just helping him out but he said he is just gonna order a pcm so hopefully that fixes it?
 
With battery disconnected, do a resistance check with an ohm meter between pin 6 and 14 at the data link connector. You should read approximately 60 ohms. If you read 120 ohms you likely have a terminating resistor open. In my 2007 ranger the resistors are 1 in engine computer and the other in the instrument cluster. Be very careful proving data link connector- do not want to spread terminals. On my truck at the computer itself pins 11 and 23 are approximately 60 ohms.
 
Thank u very much i will try that. The dvom i have is a cheapo one. Do i set the meter on 60k & if so what should the meter show? If set at 60kohms will it show 60.0 on the meter or 6.0ohms or smthen? After running a new wire from the pcm to the starter relay the meter now shows 0.L with the red probe on the wire & black probe to ground. Does that just mean there isnt a short to ground anymore? The meter also shows 0.L when the probes aren't connected to anything. Before i ran a new wire it was showing 13.2ohms with meter set at 60k but it showed 11.4ohms with it set at 600k which was confusing to me because i thought it should basically just move the decimal point? Thank u for your help!
 
You do need to sort of know what value you are looking for and set the meter for the correct range before you do any testing. If you do not know what to expect, always set the meter low. If you are too low, the meter will usually say "OL" which means you are out of range. Just like if you have the meter setting there with the leads not touching.

If you get "OL" then turn the meter up one range. If you get "OL" still turn it up another range. till the meter finally starts reading a value. The nicer meters have auto-ranging.
 
Can I just add a quick suggestion here? Since different meters behave differently sometimes, just for a baseline, set the meter to any resistance setting and make a mental note of what's on the screen with the probes not touching each other, then touch them together and make another note of what you see. It should read 0.000 or 0 or something very close to zero with the probes shorted (if it's more than 2-3 ohms the probes might be bad).

This all just to make sure you know when you're seeing an open circuit or a short circuit.

Also, the reason your readings were different was because the higher up in range you go, the less accurate the measurement is going to be when you read a low reading like that. Any settings on your meter lower than 60K? I'd want to be down in the hundreds or thousands of ohms at most to be measuring values below 200 ohms.

Also, with most meters, the number you get on the screen is the actual number- it'll just be more accurate the lower range you use (that isn't too low).
 
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The resistance was more than 5ohms so i ended up running a whole new wire but i still have no crank no communication. I really think its gotta be the pcm itself. Its actually a buddys truck & im just helping him out but he said he is just gonna order a pcm so hopefully that fixes it?
How many ohms does your meter read when you short the leads together?

How many ohms did you measure end to end on that wire? Those readings might give clues as to what the fault is.

FWIW I wouldn't throw a computer at it until I fully checked out the wiring.
 
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