1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Getting the U0155 code

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Steelholder, May 5, 2023.

  1. Steelholder

    Steelholder Junior Member

    Joined:
    Oct 25, 2022
    70
    17
    0
    Location:
    Encino
    Vehicle:
    2010 Prius
    Model:
    Three
    Hey all, after an oil change yesterday I noticed that my gas meter had gone from around 3/4 full to fully topped off. Seemed a bit strange but ignored it until my drive this morning, it was still full after about a 20 mile drive(has gone down one notch since). It's throwing code U0155. Some type of loss of communication, aby tips on where to start?
     
    #1 Steelholder, May 5, 2023
  2. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    23,332
    15,111
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    U0155 is some ECU in the car saying it can't communicate with the meter cluster.

    Turns out there are several ECUs in the car that normally do communicate with the cluster (the power management control ECU, the body ECU, the smart key ECU, and the air conditioning "amplifier").

    So it's useful to know, not just that you have a U0155 code, but which ECU in the car is saying it (or which ones, if more than one). Then you know which things can't communicate with each other, and then it's possible to start looking at the network diagram in the repair manual to think about where such a problem might be.

    Some scan tools tell you which ECUs reported which codes, but others just report all the trouble codes they saw, glommed together in one list. For this kind of issue, if you have the latter kind of scan tool, it may be worthwhile to upgrade.
     
    #2 ChapmanF, May 5, 2023
(You must log in or sign up to post here.)