C1203 Diagnosis procedure

PLB-389 could you, would you, PLEASE take me through the steps to clear the codes (C1203, C1345) as mentioned above. My 2005 Prius has recently thrown those codes with a C1392 included. I would really really appreciate any help. I am at a loss how to fix this.
Thank You,
Susan

What is the workshop manual?

 

@PLB-389 hasn’t been seen on PriusChat for more than six years; you may wait a long time for a reply.

“Workshop manual” is a generic term for the book that Toyota calls the Repair Manual, with detailed troubleshooting and repair procedures for all of the car’s systems. For model year 2006, it exists as a fairly expensive (and now out of print) three-volume set of printed books, with over 4000 pages, and as an electronic version, available by subscription to techinfo.toyota.com, among other sources.

To clear the stored diagnostic trouble codes (DTCs) for the electronically controlled brake system, if you don’t have a Toyota Intelligent Tester or Techstream diagnostic system, the Repair Manual gives this procedure:

4. CLEAR DTC (USING SST CHECK WIRE)

(a) Clear the DTCs using the SST check wire.

(1) Using SST, connect terminals TC and CG of the DLC3.

SST 09843−18040​

(2) Turn the power switch ON (READY).
(3) Clear the DTCs stored in the ECU by depressing the brake pedal 8 times or more within 5 seconds.
(4) Check that the warning light indicates a normal system code.
(5) Remove the SST.​

HINT: Clearing the DTCs cannot be performed by removing the battery cable or the ECU−IG fuse.
​

@ChapmanF kindly posted a diagram showing the TC and CG terminals. It’s not strictly necessary to use the special service tool (SST); any wire is fine, as long as inserting it doesn’t damage the terminals.

Just clearing the DTCs won’t actually fix any problems, of course; the DTCs and warning lights will return if another failure is detected. Clearing is usually done as part of a diagnostic procedure in the Repair Manual, or after repairing or replacing the suspected faulty part, to see if the trouble returns.

As you may know, the three DTCs you mentioned all relate to the electronically controlled brake system, and without further diagnosis, it’s hard to say whether they indicate a problem that makes the car unsafe to drive.

 

Thank You’s for your help and quick responses . I understand clearing codes does not fix any potential problems. Have a good day!!