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 to…

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.

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 intermit…

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 Tes…

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?

[image] johnlambe: How would I know whether they had fixed the cause of it (if there is a problem to be fixed) 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 vehicl…

I have seen that fault hundreds of vehicles and never tried to repair one. If the battery was weak at one time, that fault will occur. Could be today, could have been 5 years ago. Nothing to obsess over. This seems to frighten people so this might be a buying opportunity.

I wouldn’t expect the Irish National Car Test to report this: It just tests for safety and emissions. It passed the test around July 2025.

Toyota OBD Code P1604

Maintenance/Repairs

db4690 March 22, 2026, 3:37pm 2

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?

Topic		Replies	Views
Help please! Check Engine light just came on in my 2003 Dodge Caravan. It is giving the codes of P0601 and P1684 Maintenance/Repairs	10	2808	October 18, 2018
Toyota 4runner will NOT start no matter! Maintenance/Repairs toyota , 4runner	14	11676	January 17, 2013
Help with 2000 neon issue Maintenance/Repairs	3	449	March 28, 2009
2004 Toyota Corolla won't start Maintenance/Repairs toyota , corolla	10	3218	October 25, 2017
Strange Starting Problems Maintenance/Repairs toyota , starting , camry	9	622	July 6, 2010

Toyota OBD Code P1604

Related topics