No crank, no start issue?

CHUY4848

MEMBER
2010 FORD F-250
6.4L
V8
TURBO
2WD
AUTOMATIC
192,000 MILES

We recently acquired the truck listed above Power stroke a few weeks agon and it worked fine when we got it. The previous owner had one of those cheap $13.00 ELM327 Wi-Fi scanners in the obd ii. I decided to try out the revheads app (just reads your rpms to imitate engine noises over obd2). I drove it around like this for a while and it worked fine, parked it and then disconnected from the scanner. When we went to turn it back on, it wouldn't crank, start, anything, just a click. We checked the batteries, fine and the fuses seemed to be fine too. Used that same crappy scanner to pull codes and got U0101 and U0073, but then tried to scan them later in the day and there were no codes. We got it to turn on by directly powering the starter but now it doesn't seem to want to actually move. You can switch gears, but it won't shift or accelerate to any drivable speed. Is it possible that somehow using the app with the scanner could have caused this? As far as I know the app doesn't write any data to the computer so there should have been no reason for it to cause this. And what could be the fix?

3 Replies

KEN L

MASTER CERTIFIED MECHANIC
42,949 POSTS

Yep, those cheap ALDL scanners are nothing but problems for the CAN when they short out. The U0101 and U0073 trouble codes in a 2010 Ford F-250 typically indicate communication problems within the vehicle's network or data bus. These codes point to issues related to the Control Area Network (CAN) communication system, which allows various electronic control modules in the vehicle to communicate with each other.

Here's a breakdown of what each code means:

U0101 - Lost Communication with TCM (Transmission Control Module):
This code indicates that the engine control module (ECM) has lost communication with the transmission control module (TCM). The TCM is responsible for controlling the vehicle's transmission. When the ECM can't communicate with the TCM, it may lead to transmission-related issues.

U0073 - Control Module Communication Bus "A" Off:
This code indicates a general communication problem on the vehicle's CAN bus. It means that one or more control modules on the CAN bus are not communicating properly. This can result in various systems and components not working as intended.

Possible causes for these codes include:

Faulty wiring or connectors in the CAN bus network.
A malfunctioning ECM, TCM, or other control modules.
Issues with the vehicle's battery or power supply.
Electrical interference or noise on the CAN bus.
Software issues or a need for updates in the control modules.
Since both codes are related to communication problems in the vehicle's network, it's likely that they are connected. Diagnosing the exact cause of these codes can be challenging and may require specialized diagnostic equipment to scan and monitor the vehicle's network.

Please go over these guides and get back to us.