This is a common problem when the unit goes out, it should be replaced, but to make sure let's check the grounds to the unit.
Here is a wiring diagram (below) to help with the testing.
If the messages are all garbled when the failure occurs, it could be an indication of internal fault with info display/instrument cluster. It could be temperature influenced, or intermittent with it's own circumstances for failing.
Please run some tests and get back to us so we can continue helping you.
Images (Click to enlarge)
Saturday, June 10th, 2017 AT 11:46 AM