I bought a 2002 Prius about a week ago for just enough money to learn from it should it turn out to be a bad investment. The MFD is not working, but there's an after market radio in the car and when I pulled it out, I can see what might be the cable for the MFD and original radio. The monitor shows the Toyota logo and then "audio off" and nothing else. The Kenwood KDC MP145 only gives me a "PROTECT"(and I've tried every reset, but I haven't cut the speaker wires yet) so I'm going to permanently remove it if I can't figure it out. I confirmed that the fuses were good and then I ordered a radio harness so I can return the car radio to the factory configuration. During my pre-buy inspection, I ran my OBDII scanner and received only a P3000 misfire code, along with the corresponding cylinders. It was all four cylinders at first. I took a look at the ignition coils, but I didn't remove the plugs. Then after I put them back, making sure they were properly re-seated, the misfire was just the last two cylinders and now just the last three. I've ordered new coils and plugs and am awaiting their arrival. Is there anything else I should check in the meantime for either problem?
Water in fuel and if so, rusty fuel filler neck at top. FF neck must be removed to see the corresponding holes.
Okay, so I changed out the plugs and coils and I'm getting no DTCs now. I've driven 11 miles over two days and I'll continue to monitor to see if any of the previous or any new codes show up.
...and the misfire's back. I suppose I could just dilute the tank by filling up with more quality fuel, but I'm curious about MDNHW11's suggestion, so I took a couple of pictures. Am I removing this entire assembly or is there a particular part I should focus on checking? Thanks for any insight offered.
Yes, it should come off fairly easily as an assembly. Once it is off, on mine the rust was at the top 2-3 inches where it sits near the body. I could not see the holes with the pipe in the vehicle. Even if it isn't perforated, it is still a chance to clean up and coat the affected area. Pics (extreme case) in this thread: Misfire | PriusChat
Protect mode usually means the speakers are blown and shorted, or, more likely from your description, the wires have a short. Here is a brief list of how to diagnose: How to turn off Protect mode on a Kenwood stereo.
The MFD has a communication line (2 wires) that comes from the Center Cluster and then to both the MFD and the original radio. With the original radio unplugged, the two wires are unterminated and no communication is possible (Radio Off on the screen, and no other information can get from the cluster to the MFD). In Gen 2, (I would imagine Gen 1 is the same) the two wires get a resistor placed across them when you replace the radio, you still get the "Radio off" warning, but all other functions of the MFD are restored. The "easy button" would be to plug the original radio back in, but be sure there are no shorts in the speaker wires (or the speakers) before you do.
Here is a link to someone else's upload of the 2003 Prius wiring diagram, I would think 2002 would be the same (not sure, I'm familiar with Gen 2) Here is an interesting discussion on Gen 1 radio install: Radio Auxiliary Install? (Looks like some sort of "Y" cable solves the problem.)
Funny thing happened in the salvage yard today... I was able to pick up a stock CD changer out of an 03 Prius, wiring harness intact. I removed the Kenwood(which will be for sale on Ebay) and I restored the dash to it's original configuration. The AM/FM Cassette worked fine, the salvage yard changer worked fine and my MFD came back to life. All for a super reasonable $16.87. I contemplated pulling the fuel filler mechanism out of the donor car, but something in my gut told me to buy it new, so it's on order. "Petunia" (yeah, I named her) is coming together. Thanks for all the help in this forum!
I'm glad your car is coming together, but be warned the reason you don't see many gen 1 prius on the road now is because they all probably have bad batteries. So make sure you're willing to invest in a battery before you start spending money to make this car all nice again.
Thanks for the advice! I paid $450 for the car, thinking at the time that the batteries were bad. I ran my OBDII scanner during the purchase inspection and so far, no sign of bad batteries. My daily commute is 80 miles round trip, so I'm pretty much a "beater" driver to work and leave my Volvo XC90 parked in the driveway. I have a simple rule; for every used car I buy, I count $300 for every month I can drive it, so if I can drive this Prius for, say, two months, having invested less than $600, I'm up. My original plan was to fiddle with this car until I came to an investment I didn't want to make and then sell it or part it out on Ebay. I'm more optimistic now. An Engineer friend(and fellow HAM) of mine rebuilt his battery pack for his gen 1 Honda Insight and he's basically volunteered to help me do the same once that day comes. I know it's probably inevitable, but I'm less intimidated by the challenge because of my friend's help. The purchase price made this car the perfect opportunity to learn. Incidentally, the 2003 Prius I found in the salvage yard was immaculate, inside and out. I wonder if it was junked for the batteries alone. It's a shame if it was. What used to be a guaranteed $6000-$8000 investment has come way down in cost.
Just one question for your little experiment with a Gen 1 Prius. Will the Kenwood be listed for $16.87 on Ebay? Or are you one of those who plans to profit off your endeavor?
Profit, with all parties pleased, is never a bad thing. I'll list it, "parts/not working", explaining the "protect" message I couldn't overcome, with the starting bid at $17, and let the market decide.
Amazing how many Prii get discarded at the first hint of any trouble; welcome to the "automobile as appliance" age. Congrats on your successful resuscitation of a Gen I! Welcome.
