Toyota OBD Code P1604

I’m considering buying a 2015 Toyota Aygo that’s reporting this DTC code: P1604 (Startability Malfunction) - Toyota P1604 Code: What It Means and How to Fix the Startability Malfunction - Daily Car Tips

(From what I’ve found online, it means that sometime, the engine either failed to start, took too long to start, or started and cut out within 2 seconds.)

I’m trying to find out how serious this is: Could it be an intermittent problem or something that occurs only in certain conditions (such as in cold weather - in the last few months; I’m in Dublin, Ireland: minimum winter temperature about -4°C.)? (Since the dealer hasn’t fixed it, maybe they tried and couldn’t fix it.)

Is it likely to be difficult or expensive to diagnose or resolve (there are a lot of possible causes of it), or is it not worth worrying about if it starts okay now?

Could it be something that is not even a real problem, such as someone having tried to start it with no fuel (dealers might keep low fuel in their vehicles)?

The engine started when I saw it. I haven’t test driven it yet though. The battery voltage was 11.6 V (measured at the OBD II port, with the engine off) when I saw it.

11.6 volts is definitely not a fully charged battery

Should be 12.6 volts ignition off

Maybe a weak battery is the only problem here?

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I can only offer what I would do. If the seller will not solve the problem then I walk away and look for something else.

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Thanks.

How would I know whether they had fixed the cause of it (if there is a problem to be fixed), rather than just cleared the code?

This seems to be reporting a problem that occurred sometime since codes were cleared (maybe just once, or many times), and I’m concerned that it might be intermittent. (I haven’t seen it failing to start myself.)

Of course, I suppose it could be a problem that has already been fixed.

As db4690 says, it could be a weak battery, or just the battery having previously been weak due to sitting unused in the dealer’s lot, and it did start when I saw it (despite the low voltage - 11.6 V).

What Is The Normal Battery Voltage Off The Vehicle?

When a car is off, the 12-volt battery should show a resting voltage typically between 12.4 and 12.6 volts. A fully charged and healthy lead-acid battery commonly reads around 12.6 to 12.8 volts.

https://www.engine-codes.com/p1604_toyota.html

Tester

Is this a current code?

Do any warning lights remain illuminated at idle?

I meant 12.6 volts ignition off is fully charged

Can you determine the battery’s age?

Are the connections clean and tight?

Since I am in the US I have no idea how your vehicle used sales work. Some dealers offer a limited warranty. Some will let you take the vehicle to a shop to have it inspected.

Another question: are vehicles allowed to pass inspections (if required) with trouble codes?

The code seems to be very elusive and anywhere from a weak battery to a failing crank sensor, weak fuel pump or not holding pressure, weak ignition system or basically anything that can keep a vehicle from starting normally…

You are rolling the dice buying this car, it could be the best used vehicle on the planet with a weak batter, to a very costly future repair bill…

If everything else checks out during a pre purchase inspection, then I would ask for some kind of guarantee (may never happen though) that the code is nothing more than a weak battery…

Good luck…