Braking reliability has not been one of Audi's strong qualities. Australia's most recent recall involves as many as 445 Audi SUVs with leaking brake cylinders. This follows an earlier worldwide recall in 2014 when the automaker recalled 70,000 cars (1,240 of them in Australia) that had potential brake issues. Five years ago, GoAuto.com reported that the affected models included the Audi A4, A5, A5 Cabriolet, A6, A7 and Q5 models powered by the 3.0-litre six-cylinder turbo-diesel engine, built between March and December of 2012.
That recall was triggered by the concern that engine oil could enter the brake servo through the vacuum lines. This would cause the diaphragm in the servo to rupture, resulting in the brake servo failing. The brakes would still work, but drivers had to apply more pressure to the pedal to stop the car.
Details on Audi Australia's latest recall
According to the ACCC, Australia's consumer and product safety organization, this year's recall of the 2019 Audi Q5 mid-size luxury SUVs came about because the wall thickness of the brake master cylinder may not meet specifications, which could cause the hydraulic brake system to fail and lead to an increased risk of an accident. ACCC reported that the electronic parking brake and its emergency braking function remain functional, however.
Audi Australia is contacting all owners of the affected vehicles. Consumers should contact their nearest Audi Dealer to arrange for inspection and repair. The brake master cylinder will be checked and replaced if the dimensions do not meet specifications. For further information owners are being advised to call Audi Australia's 24-hour toll free number, 1800 50 AUDI (2834).
Other brake recalls around the world
Audi is not alone in its brake troubles. This month, Nissan Canada recalled more than 90,000 Rogue crossovers because their automatic emergency braking system could unintentionally engage. Automotive News Canada said the recall involved 90,792 vehicles from the 2017 and 2018 model years.
The unusual thing about this particular braking problem is what triggers the sudden braking. Transport Canada, the government agency responsible for auto safety recalls, warned on its website that under certain driving situations, a metal structure like a railroad crossing or overhead sign could cause the Rogue's Automatic Emergency Braking system to activate when it is not needed. When this happens, the system would provide a collision warning, but if the driver doesn't take action, the vehicle would slow suddenly or come to a full stop.
Similar action by U.S. counterpart
Meanwhile, in the U.S., the National Highway Traffic Safety Administration launched its own investigation into the unintended braking in 2017-2018 Nissan Motor Co. Rogue crossovers. 675,000 vehicles were affected. This probe, coming on the heels of a Center for Auto Safety petition to the NHTSA in March, acknowledged the 87 consumer complaints received by Nissan regarding this problem.
According to Automotive News Canada, Nissan said it had investigated the issue extensively and after discussions with both Transport Canada and NHTSA, the automaker had notified all affected Rogue owners in the United States and Canada of a software update that would address the automatic braking problem.
Consumer Reports shed more light on the issue, saying that the Center for Auto Safety action petition was in response to Nissan's treating the braking defect as a service matter rather than as a safety problem. CR quoted Center for Auto Safety Executive Director Jason Levine, who said "The time has come for either Nissan, or NHTSA, to be sure that everyone who owns a Nissan Rogue knows about it as well." When automatic braking works as designed, he added, it's a vital safety feature.
"However, when it performs erratically and suddenly stops the car for no reason, it endangers both the car's occupants and any following cars that may crash into the unexpectedly stopped vehicle. Just as dangerous, this defect is causing some owners to manually turn off the braking feature when they start their car, eliminating its potential safety benefits," Levine declared.
According to Consumer Reports, Nissan Rogue owners whose cars are still under warranty can get the service bulletin work done at no charge to them.
If you are an engineer working on automotive braking systems, whether they're conventional systems or automatic emergency braking technologies, ask for a complimentary brake testing consultation from Greening.