2016 2.7EB 4x4 screw. Running and driving absolutely normal. The orange wrench came on randomly while driving and said check manual. Then another came up that said hill Start assist not available. I took it to have the code read because my OBD is on the fritz and it’s not logging a code. When I start the truck the wrench doesn’t show up until I have put it in drive and have driven about 10ft before the alerts start happening. Any ideas??

 

Pretty hard to tell with the little info you provided - and I'm not being hard on you. My quick guess, with no DTC information, is a wheel speed sensor issue.

 

I understand. With no CEL code showing I'm at a loss for how to get any more info. What if any info would be helpful?

 

Do you have access to a scan tool or FORscan? There are lots of DTCs that do not turn the CEL on. Any codes would be very helpful. Have you visually looked at your speed sensors? Could be a wire got pinched which might cause an intermittent problem.

 

Mine has done this once and never came back. It was when I was hunting and on a lot of snow and dirt back roads. I read the wheel sensor can become briefly obstructed and cause this. 7500km later hasnt returned.

 

My 2017 3.5EB 4x4 did the same. Came back one other time, and went away on it's own. Dealer could not determine anything because light was off during inspection. Engine light has come on 3 different times, again no help from Dealer, they said no codes in memory. Although, Truck still running ok, good performance.

 

Here are the active codes via forscan at the time of log request:
U0401- invalid data received from ecm/pcm
P0504-Brake switch A/B correlation
Any ideas?

 

U0401 - With the ignition ON, the PCM sends vehicle speed data messages to the GWM along the HS-CAN1. The GWM relays the messages to the RTM using the MS-CAN 1. If the vehicle speed data messages are invalid or faulted, the RTM sets a DTC and the TPMS warning indicator is illuminated.

This DTC sets in continuous memory if the vehicle speed message from the PCM is "invalid" or "faulted" instead of the actual vehicle speed data.

WSM says to run a RTM self-test and see what other codes come up.

P0504 - A DTC that sets when the PCM does not sense the correct sequence of the brake pedal input signal from both the cruise control deactivator and stoplamp switches when the brake pedal is pressed and released.

P0504 - Brake Switch Correlation

Description:
This DTC sets when the calibrated threshold is exceeded during a comparison test between the brake pedal switch (BPS) and the brake pedal position (BPP) switch.

Possible Causes:

• Damaged brake switch
• BPS circuit open
• BPS circuit short to voltage
• BPS circuit short to ground
• BPP circuit open
• BPP circuit short to voltage
• BPP circuit short to ground

Diagnostic Aids:
Check the state of the BOO1 and BOO2 PIDs. The BOO1 PID is normally open and BOO2 PID is normally closed.

Have you performed any work on the truck under the control panel that might have caused a wiring issue? Pinched wires? Loose connector? MS-Can runs to the diagnostic connector which is real close to the BPP switch. That is where I would look first.

 

U0401 has three sub-types which may be helpful in diagnosis: U0401:00, U0401:81, and U0401:82. All of these seem to be related to a communication on the network. The manual also says to deal with any non-network related issues, your P0504, first as these could have triggered the network error.

 

Hm. I’m not sure that I understand where you’re saying to look or what I would even be looking for. I did just run a power cable for an amp through the grommet on the drivers side which sounds like it could be the culprit.