Check engine light was on solid - so I hooked up a code reader to the OBD2. Went ahead and cleared code -- hasn't come back yet, but wanted to see what it might be indicating if it comes back on. Doesn't seem to be a common one, given my on-line research...
That is not a valid Gen II code, if that is the model you are asking about. P1121 is related to the heat storage system, coolant control valve stuck, which is common enough in Gen II. If you used a generic code reader, there are numerous cases of erroneous readings when used on the Prius.
