Drivers are broadly happy with the repairs and servicing provided by approved garages but require clearer, more accessible advice, according to analysis of customer calls to a free complaint helpline.
It is three years since Motor Industry Code of Practice for Service and Repair was launched to combat "rip-off" garages.
In 2008 the self-regulatory group set up Motor Codes, a fast-track resolution service aimed at solving motorists' concerns while the car is still in the garage.
New figures reveal that 93% of the 6,000-plus consumer calls taken by Motor Codes this year were seeking advice on a range of issues includingbreakdown cover, while fewer than 500 motorists were registering a formal complaint against one of its 6,400 garages across the UK.
Managing director Chris Mason described the 93% satisfaction rating as "hugely encouraging" and said the low complaint levels "strongly suggest that motorists should feel confident in trusting their car to a Motor Codes garage".
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