Immobilization system light flashes while driving

Was that a certified Prius mechanic? Those are symptoms of possibly serious wiring and/or computer problems which would be expensive to fix. This car needs a complete diagnosis before anyone buys it, to find out exactly what is wrong.

 

I'm not familiar with older Prius but, could it be it has SKS and the batteries in the fob are dead?

 

if the key light is lit.. it's the smart start looking for the key. maybe they started the key and left the fob at the dealership?

if the key is in the car, it should not do that. there should be 0 lights flashing while driving.. unless someone didn't buckle up.

 

With the SKS, the key fob does not need to be inserted into the slot, but if it is inserted, no battery is needed. That pretty much eliminates the dead key fob battery theory. The car should not power up without the key fob, but once started the immobilizer light should stop flashing. You need to have this checked.

Tom

 

How many fobs does the car come with? If more than one try the other one to see if the red icon continues to flash. It should not flash when the car is in operation.

A Smart Key fob has the Toyota emblem embossed in silver while a non-Smart Key fob has the emblem in black only.

When the car is IG-ON do all warning lights turn on including the red triangle master warning light and the check engine light? Does the MFD work? (this is another source of warnings)

The red flashing light might mean that the fob was incorrectly programmed or this might mean that the immobilization system was somehow bypassed. Are you buying the car from a reputable source? Was the car in an accident?

If you don't have confidence in the seller I suggest extra care, verifying that the VIN on the title matches the VIN on all body panels, on the plate below the windshield, engraved on the body in the engine compartment etc.

I think that a mechanic who is not Prius-trained will have trouble providing an adequate assessment of the vehicle's electronics, lacking the proper code reader to retrieve stored diagnostic trouble codes. A generic OBD-II reader is not adequate.

 

MFD= Multi-Function Display = the touch-screen LCD monitor in the middle of the dash

Tell them to take it to the dealer and that you want the same inspection as a Toyota Certified used vehicle would receive. If they tell the dealer they want a pre-sale inspection at the request of the buyer, the dealer does not have any vested interest except perhaps in finding problems that they can charge to repair. You can discuss the inspection report with your mechanic to determine what needs to be fixed and what does not. The seller has a vested interest in having you not find out about any serious problems, so I wouldn't go through with the deal without one.

 

Hi Kinare, welcome to PriusChat! The reason so many here have suggested going to a Toyota dealer is that the Prius is not just another car. I has quirks and requirements that only someone with a multi-thousand dollar Toyota scan tool can test and satisfy. No slam on any mechanic, but unless they can read the state of the main ECU computers (dozens, which requires the Toyota tool) you can't be sure what you're buying.

BTW, the vanity lights require the visor to be down and the mirror exposed and the switch on the light turned on. Close the mirror, light goes off. Flip up the visor, light goes off. Flip the switch, light goes off.

Good luck! I can tell you really want this car!

 

This car really needs to go to a Toyota certified Prius technician with specialized tools and knowledge for diagnosis. Waiting a day and spending $100 now could save the buyer thousands later (I do not exaggerate; Prius computers and wiring are not cheap).

 

Take it to a Toyota dealer to have it diagnosed. It could be a faulty ECU which could be expensive.

 

I hope that his idea of "fix" does not include disabling the LED icon...

This is why I asked if all warning lights turn on when you make the vehicle IG-ON. To do this, push the POWER button twice without pressing the brake pedal, starting from when the vehicle is turned off. The first time you press the button, the car will be in ACC-ON where you can turn on the stereo.

The second time you press the button, the car will be IG-ON, and you should see all warning lights appear. Look particularly for the red triangle master warning light, the amber check engine light, the red air bag warning light, and the brake warning lights: VSC, BRAKE, and the skidding vehicle. If any of those lights do not turn on, there is a problem.

In a used car transaction, the seller always knows much more about the condition of the vehicle than the buyer. If the seller is reluctant to let the buyer perform an inspection to gain information, it is reasonable to conclude that a hidden problem exists.

 

So they don't want you to take it to a Toyota dealer? I'd run away.

As others have mentioned, the Prius is a very complex vehicle. The vast majority of the time, everything is very reliable and you have no issues. If the car history is murky, that's a warning sign

Question: are these folks selling the car "curbsiders?" That is, do they buy cars at auction, perhaps Lemon Law vehicles or writeoffs, and sell them pretending to be private sellers?

The law varies by jurisdiction, I know in Utah the state requires fingerprinting of all registered new and used car dealers. In Utah, curbsiding is a serious offense

If the car was ever registered in the Canadian province of Manitoba, do NOT buy it! There is a socialist/communist car insurnace system run by the province, called Manitoba Public Insurnace, or "Autopac." It's a Crown Corporation, fully expempt from auditing

Autopac does NOT share vehicle history data with anybody else. Curbsiding is a thriving business here, and Autopac even brags how easy it is to buy a written off car at auction. A Carfax or similar report cannot determine if a car was written off in Manitoba, fixed up, and resold as "ok."

So caveat emptor (buyer beware). I'd try to make an apointment at the Toyota dealer, wrangle another test drive from this couple, and send the car straight to the dealer. Ask in particular to look for evidence of crash damage and quick repair

 

Step on the brake and push the power button again to switch to Ready mode. Simply press the power button again to cycle off.

As for looking at the car tonight, you seem to be missing what most of us have suggested, or perhaps you are simply resisting the suggestions. Either way, I'm going to beat you over the head and state this point blank: I wouldn't spend a dime on this car until it has been thoroughly inspected by a certified Prius mechanic. This means taking it to a Toyota dealer and paying the bucks to get it inspected. It may cost money, but nothing compared to the loss you may suffer if you skip this step. The Prius is too complex for your average mechanic; they simply lack the tools and training. Get it checked.

Tom

 

If the 2004 still has the powertrain warranty in effect for 25K miles, this implies the odometer reading currently is 35K miles. Note that the powertrain warranty has a five-year duration so it may expire as soon as late 2008, depending upon the date of first sale.

Press the POWER button a third time, to bring the car to IG-OFF (the car will be turned off).

The immobilization system light should be flashing red when the car is IG-OFF. Once the car is in any of the other modes, the light should turn off.

If your car is equipped with Smart Key, you will see the amber key icon come on only if you and the Smart Key leave the car in any mode besides IG-OFF. The car will beep to warn you that you are leaving the car powered up.

When IG-ON, you should see the red air bag light come on momentarily. You should also see the amber MAINT REQD and snowflake icons come on momentarily.

The BRAKE, VSC, ABS, circular brake icon, and skidding vehicle icon should come on and stay on. VSC is an option; it is possible your car may not have that especially if you don't have the Smart Key option.

The door ajar light should be on if a door is open. The seatbelt light will be on if you don't have your seatbelt buckled.

I am wondering why a low-mileage Prius was sold at auction instead of kept by a Toyota dealer for resale. If you are not planning further inspections, I advise you at minimum to look for the VIN labels that can be found on all major body parts including the doors, the fenders, the hood, and the hatch. If you don't find a label, that means significant body work has been performed.

Further, if you open the hood you will see a black plastic cowl assembly that runs across the rear of the hood compartment. On the passenger side you will see a little access door that can be pried open. If you open the door you will see the VIN engraved into the body. This should match the VIN labels and the VIN below the windshield. If any numbers don't match that is a big warning sign.