My car wouldn't start
 

Hi guys,

This morning I tried to unlock (keyless) the car but It didn't, so I had to do it manually because there was no power at all and the battery was completely dead.

This is strange because I recently put a brand new battery on.

I gave It a battery boost, the power came back on and I tried to start but It didn't. All I could hear is tuk tuk tuk noise.

My neighbour thinks, I need a new starter. I don't think so because I recently put a brand new one as well.

One more thing, as soon I put the battery boost cable off, everything completely died again.

Before I take it to the mechanic, I would like to hear from you guys. I hate taking it to Mazda dealership because they give me a heart attack with their charges.

What do you guys think has happend to it?

If you're hearing the starter click repetitively it's most likely insufficient battery power and therefore not fully pulling in the starter's solenoid to engage the flywheel. Or it could be the starter motor. Go with a known good battery as your first troubleshooting procedure (chargers have the voltage, but may not have the amperage needed) - there's starter motor electrical inertia (aka 'locked rotor') forces to overcome.

Your alternator may not be putting out the proper ~14 volts to give you a good continuous recharge of the battery. Volt-meter the battery terminals with the car running. Also check the tension on your alternator belt; it should deflect about 1/2" or less under good thumb pressure.

Regular batteries that have been fully discharged may no longer hold a full charge, that's why "deep cycle" batteries are available if you have say aftermarket audio that draws considerably more than stock.

A simple thing, but make sure your trunk/boot is fully closed, as even slightly ajar will cause the trunk light to come on and has drained many a battery overnight.

Thanks for your reply

Why do you think It wouldn't start even with a boost?

You replied prior to my edit. I too often hit send and then find I want to elaborate - like now. ;)

"Go with a known good battery as your first troubleshooting procedure (chargers have the voltage, but may not have the amperage needed) - there's starter motor electrical inertia (aka 'locked rotor') forces to overcome."

Or you can jump start off another vehicle while it's running.

I did jump start off with another vehicle (That means giving boost to the batter via cable from another car's batter?). That did give life for a little bit, lights and stuff came on while It was still attached but as soon I took it off , everything went completely dead.

Should take out the battery and get it charged fully and then try starting it ?

Huey, that's exactly what happened. My trunk was left open for two days straight.

Are you saying, I should put a brand new battery right away and see If that works?

Most likely Yes. Again, as you fully drained your presumed non-deep cycle battery it may no longer be capable of holding a full charge, although I have done similar once and been able to recharge.

Can you borrow a known good battery just to prove this out before you spend more money? Although if you were able to jump start off another vehicle obviously your starter is ok.

Have you tried trickle charging your present battery overnight (charger lowest amperage setting)? Fast charges don't build up necessary battery capacity. It takes time for the electro-chemical reaction to properly do its thing.

Remember to check your alternator output if/when you get a new battery.

I'll bet you never again forget to close your trunk securely. ;)

well if you can jump your car and have it running and then disconnect the cables while the car is on and it dies immediately, i would look to having a dead alternator and possibly a dead battery (might need replaced as mentioned above). the alternator should provide power to keep the car running with some left for charging the battery.

^ the vehicle runs off the battery (@12v) with the alternator recharging the battery (@~14v). The alternator itself doesn't have sufficient capacity to run the vehicle.

Not true. The battery is used to start the vehicle and power the car when the engine is not running. Once the engine starts, the alternator powers everything.

Not sure if you did this or not, but once the other car is connected, wait quite a few minutes until you try to start your car. The running car will begin to charge your battery a bit. I've had plenty of times when it seemed like the jump wasn't working, but after 10 minutes of waiting, the car fired right up. Once your car is running, it won't hurt to leave the cables on for a while just to help things out a bit.

I was still thinking the topic subject starting. To start you need the battery's 'cold cranking amps.' ;)

Actually that's not quite true either. The two work in tandem. The alternator recharges as the power is drained from the battery. The battery acts kind of like a large capacitor that can supply bursts of power (say when a load is added, such as switching on your headlight), whereas the alternator is more of a steady state supply of voltage. Thus there are no huge cables running from the alternator. I had an alternator literally catch on fire and the wires melt off, and I was still able to drive the car home (about 15 miles), but the battery was nearly dead by the time I got home.

Volts are nice, but amps rule (kinda like torque does the work and Hp gets the credit). ;)

Anyway, back to the OP - check the alternator output and try a known good battery.

actually your alternator will run the whole car. if you disconnect your battery while its running your car will run until you shut it off.

to the op, if your car started off a boost then your starter is fine. if your still getting the ticking sound when your while your car is boosted then you either have a bad connection on the boost cables or your starter is actually pooched.

the thing to do is to trickle charge your battery overnight or possibly a couple nights.

disconnect it from the car
trickle charge it
then hook it back up after the charge and try to start it again.

if this doesn't work you can bring the battery to an auto store and usually they will test your battery for free. they can usually load test your battery which will put a load on it for a certain amount of time, the result of that will tell you if your battery is is still good or not.
the worst case is you will need a new battery.

I've tried to be accomodating but let's stop all this 'alternator runs the car' misinformation.

Of course electrically it can keep the engine running after start, but that's not what it's designed to do.

The alternator is designed to recharge the battery. The battery has the capacity to start the vehicle and load balance draws/spikes in operation.

Otherwise, great insight and suggestions all.

right. just to clarify, i was saying from a troubleshooting standpoint, that is what should happen. the car dying after getting a jump, then removing the jumper cables should not happen.

Hi guys,

I successfully started the car.

The jump start didn't work the first time. However I went to the neighbor hood Mechanic and explain the situation and he came over with a more powerful battery and the jump start worked this time.

However, as soon I shut it off. I couldn't start it again. He gave a jump start once more and asked me to come to his garage.

So I drove about 10-15 kms. That charged up the battery nicely. This time I shut it off and started it back on again, It worked.

Now It's working nicely :)

Do You guy think, I still should be concerned about the battery? Have it changed? Mechanic told me It's fine now.

I talked to Mazda, they changed the battery last year and It's still under warranty but they will still charge $110 replacment fees so I'm hesitant to go there.

What do you guys suggest?

That's incorrect. If you check the amperage output of the alternator you will see the output go up as you add load, it doesn't get it from the battery. There is no need for a huge cable running from the alternator as it is not used to start the engine. Of course you were able to drive home on the battery, you took the alternator out of the system.

I recommend the Sears Diehard "Platinum Plus".

Concur, Optima Red Top (Yellow Top if aftermarket audio, etc.) or Sears Diehard Platinum Plus (I forget at the moment the OEM rebadge, but they're top notch).

See EDZRIDE, we can agree on something. ;)

I knew that; actually, we agree on quite a few "things" :yesnod:

Are you guys telling me that I still should get a new battery?

Just for your own piece of mind; take the car to Sears and have them load test the battery.

Thanks very much guys for all of your help.

I will get it checked at sears :)