dkarrels
Member
Hi All,
Starting yesterday, my 2010 Ford Expedition began exhibiting an intermittent no crank/no start concern. I drove it to the auto hobby shop to change the oil; it started fine for the short trip (~5 minute drive). After arrival, it would not start -- no crank, no start, no headlight dim. I came back several hours later and it again started on the first attempt, and refused to turn over on each successive attempt. I was able to jump the 12V high-power pins on the starter relay housing to jump start it and drive home. Since then, I have been troubleshooting.
Diagnostic steps and results:
- Placed multimeter on the low power line to the starter solenoid. When turning the key to start, no voltage is reported at the solenoid. If I hot wire the starter relay, I see 12V at the solenoid and it starts fine. This, I believe, rules out the starter and starter solenoid as being the problem.
- I swapped the starter relay with other relays with no results.
- I bench tested the starter relay and it appears to work fine.
- When turning the key to start, the low power inputs to the starter relay show 9.7V-10V. I expected this to be 12V, and if I connet the two high power pins of the starter relay housing it cranks easily.
- I checked ForScan and the computer is sending a signal to the starter relay every time, indicating the computer sees no faults in the system, including the transmission position sensor.
Any ideas on how to proceed or where to check next?
Thanks.
Starting yesterday, my 2010 Ford Expedition began exhibiting an intermittent no crank/no start concern. I drove it to the auto hobby shop to change the oil; it started fine for the short trip (~5 minute drive). After arrival, it would not start -- no crank, no start, no headlight dim. I came back several hours later and it again started on the first attempt, and refused to turn over on each successive attempt. I was able to jump the 12V high-power pins on the starter relay housing to jump start it and drive home. Since then, I have been troubleshooting.
Diagnostic steps and results:
- Placed multimeter on the low power line to the starter solenoid. When turning the key to start, no voltage is reported at the solenoid. If I hot wire the starter relay, I see 12V at the solenoid and it starts fine. This, I believe, rules out the starter and starter solenoid as being the problem.
- I swapped the starter relay with other relays with no results.
- I bench tested the starter relay and it appears to work fine.
- When turning the key to start, the low power inputs to the starter relay show 9.7V-10V. I expected this to be 12V, and if I connet the two high power pins of the starter relay housing it cranks easily.
- I checked ForScan and the computer is sending a signal to the starter relay every time, indicating the computer sees no faults in the system, including the transmission position sensor.
Any ideas on how to proceed or where to check next?
Thanks.