Late for an appointment? Murphy's Law will dictate that something will get in the way and today it's a car that simply won't start. This has you scratching your head, however, as it doesn't appear to be the battery, but when you turn the key, nothing happens. Electrical issues aside, it's likely fuel delivery and, specifically, the pump itself. How can you troubleshoot this as quickly as possible to see if you can get on your way?

Where to Start

As with most things associated with your car, there's a step-by-step approach here, and you should start by seeing if the pump is receiving any power. Turn off any distractions such as the radio and listen carefully as you twist the ignition key. You should hear a buzzing noise that goes off after a few seconds, and if so, this is the fuel pump trying to prime the system.

Power to the Pump

If you cannot hear that buzzing sound, you need to see why the pump is not receiving any power. Begin by looking at the fuse box and isolating the particular fuse. Sometimes you will need to refer to the owner's manual to see which one it is if they are not labelled very clearly. If the fuse appears to be okay, you should then check the relay which is normally fairly close to the fuse box. It may be difficult to determine if the relay is functioning, but you can interchange it temporarily with an adjacent relay to see if this fixes the matter.

Security Shutdown

Is your vehicle fitted with an anti-theft system? If so, a small light may be blinking on the dashboard if it has inadvertently armed itself. In this situation, power will be disabled to the fuel pump in order to prevent the bad guy from getting away with your wheels. This could be caused by a defective chip or even a dead battery in your keyless entry fob, so you need to see if that is the issue before rebooting the system.

Something Else?

These are some of the more obvious issues which are relatively easy to fix and could get you on your way. Unfortunately, there are a number of other potential problem areas including the possibility that the fuel pump itself has gone bad. If this is not the first time that you have encountered this type of issue, then you should certainly refer to a professional mechanic for guidance. Perhaps it's time for you to replace your fuel pump completely so that you are not late for that appointment again.

For more information, contact your local Denso authorised dealers.