Diagnosing Airbag Fault

Why airbag warning lights come on

Airbags no doubt save many lives and prevent serious injuries, but they have their faults that often need specialist knowledge to rectify.

One such common fault is an SRS warning light coming on for no apparent reason.

This happened recently to a neighbour’s car. His daughter had borrowed the car as hers was in for a service and he was none too pleased when she returned it with the light glowing.

Prime suspect is a poor connection at the seatbelt pre-tensioner. If side airbags are fitted, suspect the seat sensor connection.

Repeatedly fastening the seatbelt and/or adjusting the seat may eventually loosen connections and eventually bring loss of contact.

Rectification is a simple matter of cleaning and remaking the connections and mostly this may be done without activating the SRS. However, check with a specialist first.

As with most SRS work, it is recommended that the battery should be disconnected and left for at least half an hour before disconnecting anything else.

But do not forget to have the necessary security codes before disconnection.

Even allowing the battery to go flat might mean a trip to the franchised dealer to reset the light.

In the good old, bad old days, buying a cheapie was not so risky. We had contact-breaker ignition, braking systems (non-ABS) were easily understood and simple enough to service and electronic control units were virtually unheard of.

Now, repairing a faulty ABS could prove very expensive and even minor checks could hit your wallet.

For example, one guy who normally does his own servicing and repairs heard what he thought was a worn hub bearing. He jacked up the suspect side of the car and spun the wheel.

Toyota Recalls 308000 Rav4 And Highlander Over Airbag Sensor ...

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The Toyota Motor Corp. has announced a recall of its 308,000 SUVs in the US over problems in sensors that control the airbags. The malfunction in sensors could lead to unintended airbag deployment. Toyota has announced that it’s recalling 214,000 RAV4 models and 94,000 Highlander and Highlander HV models over side curtain airbag issues. The voluntary recall covers some of the MY 2007 and 2008 models. These vehicles would need a new curtain shield airbag sensor assembly replacement. The Japanese automaker is alleged to have received reports of minor injuries caused by the airbag fault, prompting the company to conduct a voluntary recall.

The roll-sensing curtain shield airbag system contains two sensors that detect roll angle. In case any one of the sensors malfunctions, the airbag warning light illuminates indicating that the side-curtain airbags won’t work in a roll-over, but the airbags are still be available in the event of a side collision. If both sensors fail at the same time both the seat belt pretensioner and the curtain shield airbag automatically get activated.

According to the Toyota, vehicles equipped with this system have been sold only in the North American market. Vehicles sold elsewhere are not equipped with the same system for rollover sensing.

According to the Toyota, problems in RAV4 and Highlanders are as the following:

* Two of the airbag sensors meant to detect vehicle roll angle could malfunction in specific models sold in the North American market * Part of the seat belt affected is the pretensioner that automatically tightens in the event of a crash

Toyota will inform the car owners of the recall in May 2011 and instruct them to take the vehicle to a local Toyota dealership. The customer can approach the Toyota dealer for free repairs on his RAV4 or Highlander. The technician will do the necessary tests and replace the defective roll sensing sensor assembly free of cost to him.

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