Prius Gen2 Blinking Lamp Example

Time to give back a little bit.

This is a short video of my 2007 Prius blinking the (!), ABS, and VSC indicator lamps on the dashboard cluster while OBD pins 4 and 13 were shorted together and the vehicle is in READY mode.

I annotated the video with the number blinked out by each sequence so that you can understand visually how to decode your blinking codes. Focus on one and only one indicator at a time, don't be distracted by all the other blinking around it. The trick is to write or type each number as you see it without taking your eyes off the lamp or else you miss the second number of the pair and have to wait for it to cycle around again.

A voice recorder would allow you to speak the numbers as you see them without taking your eyes off the lamps.

Word has it that they blink the codes repeatedly and indefinitely, but I'm pretty sure my (!) indicator just gave up after about 4 minutes or so because I was so slow in recording things. YMMV.

Once you get all the codes for each indicator, look them up using your subscription to techinfo.toyota.com under your model year which should narrow it down close to the source of the problem.

 

Actually, I wouldn't mind a knowledgeable person advising me what (!) codes 69 and 57 indicate. Thanks!

All research and signs point to the well-known brake actuator problem, but it is now 3+ months since that Extended Service Bulletin expired and I started driving the car more than 10 years before that anyway. So this is all on me. The accumulator pump runs for 8 seconds, then shuts off for 8 seconds, rinse, repeat. The brake action seems fine to me. Every time I've taken the Prius to my trusted local shop and ask them to check the brakes while it's there, they always tell me the brakes are fine. I guess the regen braking saves tons of wear on the friction brakes.

The 12 Volt battery is not factory fresh, but under headlight load in IG-ON it holds steady between 11.6 and 11.7 Volts. I really don't get why that is of concern when this problem manifested itself while driving in READY mode, which is powered by the inverter, so what difference does the battery voltage make at that point?

Also, if these sensors and computers freak out right on the ragged edge of 12.0 Volts then that points out some questionable design choices on the part of the usually savvy Toyota engineers. Run the stuff at an internally regulated 5 Volts and the electronics don't care if the battery voltage is 12.4 V or 11.4 V or 10.4 V. This is really not rocket science.