Citroen C4 Picasso full automatic AM6 C4 Picasso epb Hi got a 2014 C4 Picasso diesel auto and it's been 2008 Grand Picasso - Faulty Gearbox - Electrical fault The car juddered, beeped and died and would not restart, it was showing anti-pollution fault, gearbox fault & handbrake fault one after the other. The handbrake did operate manually. I got assistance to push it into the road works to allow the traffic to flow. I checked the warning logs and all of the above faults were listed. Joined: Tue Sep 15, 2015 6:38 pm. x 5018. Re: ET6G gearbox fault. by GiveMeABreak » Fri Jul 24, 2020 3:52 pm. Hi Steen. Your Gearbox ECU has gone into a backup mode caused by the fault. P171A means there is coherence fault in the CAN and brake wiring and this will prevent gears above third being selected. Suspect areas: Gearbox ECU. This is not a fault I can just talk you through as it needs first all the wiring checking and continuty checks then pin signal checking to and from various control modules it will need to go to Citroen dealer or an auto electrical specialist to resolve this problem. I told you some basic checks you can do above. 2. Automatic transmission. When choosing a second-hand Citroen C4, pay attention to manual gearboxes: they work properly and are stable for more than 100 thousand km. And the owners have many claims to automatic transmission AL4: the first signs of death it reveals already at 50 thousands km. My 1.6 HDi Manual Gearbox has it. It works a treat. No need to apply any 'special' pressure to the pedal. I just hold the car on a slope with the footbrake, then release, and all the time it takes to move to the throttle and then find the biting point on the clutch, it holds the car. Citroen c4 Picasso with semi-automatic gearbox, when cold staring when you try to drive of it shunts like in the old days when you had to pull the chock out to get the car going. When its warm ( car r … read more I have a 2003 citroen xsara 2-0 hdi auto 5 door saloon it has an anoying gear box fault after starting the car from cold and runnig it for about ten minuts the sport & snow lights come on and the car … read more The gearbox is an automated manual, and needs to be driven with care to smooth the changes, particularly first to second. We've had it 3 years it's been making the banging noise for a couple of months and it seems to be getting worse. Could be engine mounts. What to look for when buying a Citroën C4 Picasso 2013 - 2018, covering common problems to check for and overall vehicle reliability. Incorrect gear might be selected. Common Citroen C4 OXJ8d.