Have you tried a jump start and checked for codes?

 

I have tried to jump start it. No codes were found, but I don’t have a high end code reader. I also checked the starter relay, all the starter fuses, and the ignition switch. The security system seems to be working properly, the security light goes out when the key is inserted. I have tried a spare key. I did not check the NSS. (But I did try starting it in neutral) I figured that I would not be getting 12v at the starter solenoid if the NSS was bad. If there was a problem with the pcm would there be 12v at the solenoid?

 

How do you know the starter is good? Did you take it out and test it on a bench?

 

Initially, thinking it was a bad starter, I replaced the starter. That didn’t change anything. Then when I couldn’t solve the problem, I thought maybe I got a “bad” refurbished starter. I took the new starter out and bench tested it. It runs fine, although I didn’t have all of the fancy monitoring equipment like in the video. Also the car never gave any indication that anything was failing. It was cranking fine, until it didn’t.

 

I suspected a bad connection between the cable that supply’s 12v to the solenoid and the solenoid. I had my wife hold the key in the start position while I tried to move all the wires around. I tried a jumper between the male and female ends of the plug to eliminate a bad connection.

 

Sounds like a starter but it may be that one or the other wires to the starter cannot handle the load to be able to carry the required current (ie......... corroded wire or most strands broken wire). Maybe do a voltage drop test. Voltage is one thing but current is another.

 

Voltage at the battery is 12.6. Voltage at the solenoid when the ignition is in the start position is 12.1v

 

What happens if you jumper wire between the larger always hot wire on the starter and the smaller solenoid wire on the starter also? Maybe you did that already but I missed it.

 

I was just able to do that now. When I jumper the always hot terminal to the smaller solenoid terminal the starter cranks as it should. When I plug the , only hot wire when the ignition is in the start position, back into the solenoid and try starting I get nothing. I have checked the voltage in that wire several times. I’m getting about 12.4v in that smaller solenoid wire when the ignition is in the start position. I don’t really understand how the PCM relates to all this or if it even does. Could there be a problem with the PCM?

 

The voltmeter doesn't allow for any current flow. Crimp a couple of leads to a head light- or fog light bulb and use that as a test light to check power on the starter solenoid wire. The bulb draws 4-5 amps to simulate the load of the starter solenoid. Compare the bulb brightness when powered by the starter solenoid wires (if any) vs. touching the leads to the battery.

 

See attached wiring diagram for an 07. I am almost certain the PCM is not involved in the CRANKING circuit unlike a lot of the newer cars. 12.4V on the small wire seems fine when it is in the crank/start position. I was curious about the load carrying capacity of the small solenoid wire and that is why I was asking about doing a voltage drop test. When you measure the 12.4 volts in the smaller wire, it it attached to the starter or just "loose"? ie under the solenoid "load".

 

When I’m measuring 12.4v on the small solenoid wire it is loose (not attached to the solenoid). When it is plugged into the solenoid there is no bare wire exposed to test.

 

I suspect when it is under "load" by the solenoid, the voltage will be much lower than 12V and it cannot cannot carry the required current. Wire may be corroded or most of the strands could be broken or the starter relay is fried or or or............

 

I think you are right. Tomorrow I will try putting a new starter relay in, even though I tested it, maybe it passed my test but it’s not allowing all of the current through. I would really be happy if that solves the problem. If it’s a problem somewhere in the wiring, I think I’m going to have to pay for it to be someone else’s problem. I’ll let you know what happens. Thanks for your help!

 

NP! Check the contacts for burning/blackness on the starter relay also. Good luck and let me know!

 

Today I replaced the starter relay and it started right up! Yay!

I originally tested the starter relay and ruled it out because it passed. It clicked and their was conductivity through the switch when power was applied. I took the old relay apart, the contacts were black and dirty. Apparently it worked well enough to pass my test, but wasn’t allowing enough current through. I probably could have cleaned it, but at this point I’m happy to pay $38 for a new one.

Thanks again for everyone’s help!