Ask an expert

In recent times we have noticed vehicles we are following failing to indicate their intended turns.

One such vehicle I followed and eventually spoke to the driver about this.

To their surprise they discovered the rear indicator bulb had failed.

I then pointed out the difference in speed of the dashboard warning light when indicating left or right. The speed of the warning light was almost double on the side where the bulb had failed.

How common a problem is this Jack, excluding those who do not use their indicators at all?

How is it that drivers do not know these simple facts and how many incidents occur because of this?

Janet

From the "Ask Jack" archives - 27 January, 2010

Like a light bulb in your house, an indicator bulb on a car can fail at anytime without warning.

The increase speed of the drivers warning light is a very good indication one of the bulbs has failed however, some drivers are more alert and observant to these things than others.

The checking of lights is part of a WoF inspection and I would like to think part of the regular servicing regime by garages.

Police officers no doubt keep a watchful eye on cars when turning to ensure their indicators are working and bring it to the attention of drivers if there are any issues.