Diagnose and fix U0404 Jeep Grand Cherokee, Jeep Commander
The U0404 Jeep Grand Cherokee, Jeep Commander trouble code is quite common. It’s defined as; U0404 Implausible Data Receiver from ESM.
The electronic shift module (ESM) is located in the console and connects to the shifter mechanism. It reports a digital signal to the transmission control module to tell it which gear you’ve chosen.
Diagnose U0404 Jeep with a scan tool
Connect your scan tool and find which gear the ESM is reporting to the transmission control (TCC). Move the shifter and watch your scan tool to make sure the gear results match what you’ve selected. If there’s a mismatch, the problem is in the ESM.
IF you don’t have a scan tool, you’ll have to assume the problem is with the ESM and either replace it or try to clean the terminals.
What causes U0404 and ESM failure
Because the ESM sits next to the shifter, it collects debris like hair, coffee, soda, dust and dirt. Before replacing the module, remove it and clean it. Use contact cleaner and a pencil eraser to remove all corrosion from the contact terminals.
Next, remove the case of the ESM and check for the presence of soda, coffee, etc. Clean off all traces of debris. Then reassemble, clear the codes and see if they return.
If you can’t clean the ESM, purchase a refurbished unit. The cost less than $200.
©. 2019 Rick MuscoplatPosted on by Rick Muscoplat