Have a Car Question? Ask a Mechanic Online.
what type of vehicle are we looking at?
Are you there?
Yeah I'm Here it is a 2005 ford F150
Are you there ?
If you were to turn the headlights on, and then try to crank the engine, do the lights go dim? I'm trying to igure out whether it is a starter issue or a starter control issue
What size engine?
4.6 in think or 4.2
4.6 I think or 4.2 No the lights do not go dim
Ok - so the starter is not engaging - here's a diagram -
The powertrain control module supplies ground to the control side of the starter relay
Do you have a "security" light on?
Yes it blinks when I remove the key
Automatic transmission, I'm assuming
Have you moved the transmission range selector? It's worth a shot
Ok - but no security light flashing at you when you turn the key?
Have you had a look at the 30 amp fuse F101 on the diagram I sent - this should be in the underhood junction box
how about f102?
Its not aXXXXX No sec. light when I turn the key
the fuse is good the relay I dont know
I mean the gear shift lever - like you are going from park to drive
There are two fuses. How did you check them?
I looked at the fuse and it was still good the relay i cannot check
Do you have a test light, and can you get to the starter?
Not trying to be a pain in the A$$ here, but did you check both fuses, and how?
No test lighYes I can get to the starter I engaged it manualy it cranked the engine but it did not start
Give me a minuteI'm typing for my husband and he just went out to the truck
OK - no problem! I think there are a couple of problems with the truck
I pulled out the fuse that says 101 on it fillament is still good
He pulled out 101 and 102 and there both good
the fct that it will crank over but not start is going to complicate matters
This is a long shot, but are you using a spare key versus an original?
This is lokking more like a security issue.
The original same key as always
Also, we are going to need to check for spark soon, which is a pain
Let me look into the security system
Can I get a 100% verification on the engine? Is it a v6 or v8?
He wants to know where to look to find out this is a new truck
for him so he's not sure
Might be on a sticker under the hood, on the rad support, or on the underside of the hood
Ok give me a min. I'll go tell him
If you have the serial number, I can figure it out...
looks like a 4.6 liter v8
Yep he just figured that out
I think we can only go a bit further without high tech equipment and scan tools
No test light... do you have voltmater?
Not now but he has access to one at work tomorrow
I don't have one of these trucks in front of me, but could he swap the starter relay for another one that is in the fuse block - say the horn relay if it will fit?
Yeah he will go out and try so it could be a few minutes
He's still out there sorry Thankyou for your patience
With this starter circuit, power comes from the central junction box to the ignition switch from the ignition switch,through the transmission range sensor, and to the engine control module. If the engine computer doesn't think the truck is in neutral or park, it won't energize the starter solenoid - this is why I asked if he had moved the transmission shifter back and forth a few times
He tried changing different fuses in both 101 and 102 still nothing. He did move the shifter back and forth a few times and he also tried the spare key
with a test light or a voltmeter, i would wan to know if power is getting to the solenoid terminal on the starter - the smaller of the two connections at the starter
I don't know that I can guide you much further. Would you like me to release the question to other experts?
He used a wire from one to the other and got the engine to crank with the ignition key on still did not start he wants me to ask you about the fuel pump shut off switch
There is an inertia switch - think it is behind the passenger's side kick panel. Would cause no fuel pump action, but no a no crank condition
but not a no crank condition
There is a reset button on the switch
Ok thank you for your help and no we will not need another expert at this time . Thanks again for your patience and yes he already tried that reset button. Have a nice night