(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.
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.
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.
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…
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.
They offer a 3 month warranty on the engine and gearbox only, which seems common for older cars here. (Probably not much good for this potential problem.)
And the dealer gets some Google reviews suggesting that he would sell a car with a known problem (I think most dealers do) (3.6/5 overall Google Review rating).
But he says that he will let my mechanic inspect it on his ramp, so I intend to do that.
It reported this when I read all DTC codes yesterday. I don’t know how long ago it could have been reported (or whether my OBD2 reader can report when codes were last cleared).
I don’t think the check engine light came on, but I’ll have to check again when I go to test drive it.
The battery doesn’t seem to have the date of installation marked, and looks like it could be anything from 2 to 5 years old, judging by the space for marking it. The dealer might have a receipt or record in the service history. (I see that it has a 3-year warranty.)
The negative terminal connection looks good to me. I didn’t lift the plastic cover on the positive one.
Is it just me or does that battery look way to small for the vehicle, looks like the hold down comes out past the battery… Looks like the wrong group number… The lip for the hold down is on the wrong side of the battery…
I test drove it. It initially showed a ‘check engine’ light and battery warning. But after driving it and stopping the engine, the battery voltage was 12.4 - 12.5 V, so I think it just needed to be charged (and could do with being charged more).
My OBD 2 reader shows 255 “warm-ups since codes cleared”, so I suppose that’s the period in which the P1604 could have occurred.
Regarding the size of the battery, as db4690 says, this is a small light car with a 0.998 litre engine. My current car (2002 Peugeot 106 1.125 litre) is close to the same size and weight and has a similar size battery. (There’s less space around it, maybe because of the slightly bigger (but lower power) engine, and 2cm narrower car.) And maybe they just didn’t need that space for anything else. (The Aygo’s 3-cylinder engine doesn’t take up much space.)
