codes and what they mean....

These are codes that indicate faults with components connected to the MFD (Telephone, Bluetooth, Radio unit, CD player, CD Changer, XM tuner, etc). They are not anything useful for determining any problem with the ICE, ABS, VSC, TRAC, HVAC, etc. For these codes, you need a Prius capable scanner. Some Pep boys, Advanced Auto, etc have Prius capable scanners, so seek out one of those.

 

Any indie hybrid repair shop can read your codes, the dealer can too. Toyotas, and Prius specifically, have a different flavor of OBD2, and the scanners the auto parts stores use are not the best for our cars.

Unless you get a min VCI and install Techstream (a pirated clone) on a laptop, you can't read them yourself. Google mini VCI to learn more.

If the car is performing okay, a likely fault that would set this situation could be the the inverter coolant pump . You can check this by looking in the reservoir for the inverter coolant system. The coolant should show motion, and you may be able to hear the pump, it's on the Driver's side front, just below the the big aluminum inverter box. The pump is a wear item, over its long 200K mi. life, my 02 has had two replacements. They're relatively cheap, btw. Toyota suggests that keeping the inverter cool is paramount. If the coolant or the inverter gets hot enough, the car won't start. (mine died on a trip, 1300 miles from home.)

 

P1636 is a code from the engine's ECU, telling you it didn't hear from the HV ECU for at least 1.5 seconds

P3002 is a code from the battery ECU, telling you it lost communication with the HV ECU.

So far there's a bit of a pattern. The HV ECU lives under the carpet at the front passenger's feet.

P3006 is the only code that says anything about the battery; the voltage differences between blocks got larger than the battery ECU likes to see, and it's been seen happening in two separate trips.

So that does tell you that your battery is no spring chicken, but that's a sort of down-the-road consideration next to finding out why two different ECUs have been having trouble talking to the HV one.

All this is covered in the repair manual. There are troubleshooting steps for the P1636 on pages DI-146 to DI-147, and for P3002 on pages DI-326 to DI-327. (Those are page numbers in my 2001 manual, but for 2002 I'd expect them to be close.)

-Chap

 

Or Ebay.

 

You'd find the paper ones at helminc.com (Toyota's distributor), but they're out of print there. Yes, you might find somebody parting with a set on eBay. Both volumes plus the wiring diagrams and NCF used to be about $200 and change when in print.

But at $15 for two days' access at techinfo.toyota.com, that's an easy way to go now, and the manuals are never out of date.

-Chap