Can you experts please identify all the cases in which a Magna won't even crank while trying to start by turning the key ?

Flat battery (relay would likely click in this case), faulty transmission neutral safety switch (try in N and P) - have someone under the bonnet to confirm that when you move the auto shifter that it's actually "selecting" on the selector, located on top of the auto, faulty barrel/wiring/plug, immob unit...

Few easy things, actually charge the battery overnight and see what happens, check terminals for corrosion maybe even give them a slight rub back. What voltage is everything at when at rest? Try moving the gear selector through park down to first and then back to park.
I'm guessing you have actually tried all the normal things when cars don't start though?

Flat battery (relay would likely click in this case), faulty transmission neutral safety switch (try in N and P) - have someone under the bonnet to confirm that when you move the auto shifter that it's actually "selecting" on the selector, located on top of the auto, faulty barrel/wiring/plug, immob unit...

Thanks Wackywheelz !! Appreciate the response !!! I tried to start in both N & P, it does not crank ! What do we mean by Faulty barrel and Plug ?? How can the Immob. go bad ? Thanks again !!!!!!

Thanks dkresto !!

Appreciate the response !!! Battery shows 12.7 volts...but, charging overnight is not a bad advice !! I will do that ! But, just for my curiosity, is it possible that when voltage is below 12 or at par, does it not even give a half crank ??? it's 430 CCA battery though. My earlier battery was 530 CCA. This battery is almost 6 months old, maintenance free bought from NRMA. BTW, where can I buy a battery charger ? and for how much ? Sorry, asking these apparently silly questions cause I am a new migrant, don't know many things..... :) Thanks for your time !! Mate !!

I remember a car that came through when i was doing work experience with a local mechanic, owner said he was having heaps of trouble starting it. It turned out the terminals were slightly corroded. So grab same sandpaper or some steel wool and lightly rub away some stuff on the positive and negative terminals of the battery. But make sure you DO NOT let the steel wool touch the other terminal when cleaning. Also give inside the O's on the end of the wires a hit with the sandpaper/steel wool.
If cleaning or charging still wont make it crank its best you take it to either a general mechanic or an auto electrician.
You can get a normal battery charger from supercheap auto, or autobahn, or maybe even big W or target if your desperate. Try the auto stores and ask for some help, the people inside are usually fairly helpful with easy questions.
Oh and i think by faulty barrel/plug Wackywheelz means the ignition barrel, where you put the key. Best bet though is to get an auto electrician to sort that out if you don't feel comfortable opening stuff and having a poke around.

Thanks, dkresto !!! You are a legend !!! Thanks heaps !

Here's one even further left field... A friend of mine had a Corolla which would not start. It wouldn't crank over. This was in the days before electronic ignitions, immobilisers etc. I tried everything but no crankies. I had cleaned the battery terminals - still nothing. Then as I got him to try again, I saw a spark at the junction of the heavy starter power cable to the terminal lug. It turned out that the solder or whatever in the join between the cable and the terminal was stuffed. We got a blow torch and remelted the solder and away it went. Nowadays, I think that they use crimp fittings, but it may pay to check by wobbling the cable whilst someone else is trying to crank the engine. Wobble both ends - at the battery and at the starter motor.

There is an interesting development guys !!! I disconnect the -ve terminal of the battery and reconnect it ........and bingo !! The car started.....so, I thought "OK !! Battery loose connection was the issue..." So, I took it to aplace 1 km away....stopped it...restarted it....and starts without any trouble..I drive it for 5 Kms and finally after being satisfied that it's alright ...I take her home. And park in the parking garage. Clean the terminals with baking Soda water and clean the surface and nearby area alongside the battery with water directed to the bottom through a nozzle. Then before entering home, I decide to crank again...and same issue.... No start condition....... Anybody with an expert opinion ? My car's really acting funny and I am worried that it's not as reliable anymore !!!

(BTW, my car also has an LPG fuel system, does that have any effect on starting ? Car does not crank on Petrol and LPG both....)

Thanks Erad....mate !! You are very close to the problem..I really think there is some loose connection or short circuit etc in the system. I don't know where the starter motor is..but if you could post a photo on where to locate it..I may want to fiddle with the electrical connections to check if starter motor gets voltage or not... !!! Thanks heaps !! Fixing your car on your own is crazy but I just love to do it myself !!

I forget where the starter motor is, but I know that it is not really accessible from above. and I am too old an stiff to go and have a look. The starter motor is at the end of the engine, pretty well under the distributor. You have to go from underneath.

I doubt that it would be the terminals - it is more likely the smaller 12 V solenoid wiring which may have a crappy connection. As for short circuits, unless your battery is flattened, you don't have a short.

I think that you have already solved the problem - it is most likely the battery terminal(s). Clean up both, put some vaseline on them and reassemble. remember to clean up the terminal posts on the battery as well as inside the clamps.

If you want to do a rough check on your battery (it could be an internal dry joint - unlikely), next time it goes silly, turn on your headlights, fans - anything to load up the battery and then try to start it. If the lights dim then you have a lousy connection somewhere. Best of luck..... it is not easy.

I forget where the starter motor is, but I know that it is not really accessible from above. and I am too old an stiff to go and have a look. The starter motor is at the end of the engine, pretty well under the distributor. You have to go from underneath.

I doubt that it would be the terminals - it is more likely the smaller 12 V solenoid wiring which may have a crappy connection. As for short circuits, unless your battery is flattened, you don't have a short.

I think that you have already solved the problem - it is most likely the battery terminal(s). Clean up both, put some vaseline on them and reassemble. remember to clean up the terminal posts on the battery as well as inside the clamps.

If you want to do a rough check on your battery (it could be an internal dry joint - unlikely), next time it goes silly, turn on your headlights, fans - anything to load up the battery and then try to start it. If the lights dim then you have a lousy connection somewhere. Best of luck..... it is not easy.

Thanks Erad, I already tried the Battery test by trying to crank with headlights on...no dip in the brightness of Headlights so...battery is strong !!!! maybe some lose connection or short circuit...I dunno where the starter motor is otherwise, I have the whole Saturday and Sunday dedicated to it....Do you reckon if the starter motor gets jammed ? I mean in a certain position ? Is it a possibility ?

If the starter motor jams - in any position - and it gets hit with 12V, it will draw massive current. You will hear it grunt for a while , then smoke from somwhere. if the starter fails to crank the engine over, it could be something as simple as the solenoid wire. If you can get to the solenoid (the cylindrical barrel on top of the starter), try connecting a jumper lead directly from the battery. MAKE SURE THAT YOU ARE IN PARK OR NEUTRAL. If the motor cramks over, the fault is somewhere further up the line - more likely between the solenoid and the ignition barrel. If you cannot trace this at this stage, take it to an auto sparkie. Depending on the previous life, it could even be the brushes in the starter motor. I am running out of ideas. You need to start narrowing things down - the jumper lead directly to the starter is one step in a long chain of steps.

If the starter motor jams - in any position - and it gets hit with 12V, it will draw massive current. You will hear it grunt for a while , then smoke from somwhere. if the starter fails to crank the engine over, it could be something as simple as the solenoid wire. If you can get to the solenoid (the cylindrical barrel on top of the starter), try connecting a jumper lead directly from the battery. MAKE SURE THAT YOU ARE IN PARK OR NEUTRAL. If the motor cramks over, the fault is somewhere further up the line - more likely between the solenoid and the ignition barrel. If you cannot trace this at this stage, take it to an auto sparkie. Depending on the previous life, it could even be the brushes in the starter motor. I am running out of ideas. You need to start narrowing things down - the jumper lead directly to the starter is one step in a long chain of steps.

Erad...Thanks again for taking out your time...The only thing I hate as an Electrical engineer myself is to get help about Electrical faults from someone else and not doing it on my own..But, it's life and it's Automobile engineering..so, I have to give up I guess...But, you guys are most generous... Thank you so much !!

Erad, there's definitely a buzzing sound...but no smell of burning. I am curious now...about the solenoid ? What does the solenoid do ?

The solenoid is a mechanical latch which throws the pinion (small gear) into engagement with the ring gear on the flywheel or torque converter. Once it engages, the current flows to the main part of the starter. Maybe it is time for you to go to an auto sparkie and get this sorted? The solenoid is almost a mechanical analogy of an electrical relay in that you activate a pilot current in order to get the main (massive) current to go on the starter, otherwise you would be switching up to 300 amps or more.

Wow !! Erad..You are a Legend !!! Thanks so much !! U explained the stuff to me in my own way !! Great !!! This site rocks and you rock too !!! Just one more question...Would this happen if my battery is of lower CCA ? Magna user manual says starting current of 420 A and my battery has 430 at full capacity ! :( What do you say ?