DS7 - Couple of faults advice please

[spacebiscuit]

2018 DS7 HDi Blue.

First weeks on December I got the orange warning lamp with "risk of particle filter blockage. Please refer to the manual" fault. The car does lots of short journeys which I know is not ideal for a diesel, especially during the colder months. I used a code reader which returned "Warm up Catalyst threshold below threshold bank 1". So I took the car for an hour drive on the motorway, 55-65mps and on the next cold start the warning disappeared. Then a week or so later during the cold snap it has returned again.

Then this week whilst driving I got "Automatic braking" error - the brake is very briefly applied and then continues. Seems to happen in 2nd gear on an incline.

I'm not sure if the 2 issues are related - I read that a sensor used for the braking might be dirty - I've had a look but can't see it behind the front grille - is it inside the DS7 badge.

Regarding the particle filter, is this a serviceable part? I read that the warning systems on PSA vehicles are keen and if anything a little over-cautious, is this case because I don't want to cause further issues if this isn't just something I have to live with during the winter months.

Any advice appreciated - thanks.

[PaulC5]

How many miles has it done ?

The DPF can be cleaned or replaced but usually a diagnostic is then needed to tell the car it has been done.

If at about 80k miles it might be due for the DPF fluid topping up, have a look at the service schedule to check this - on our Cactus refilling is at about 80k miles and we had it done last month. This also needed a diagnostic to tell the car it had been done since the level is not measured, just calculated based on fuel tank fills.

[spacebiscuit]

has done 63k - last summer I had the AdBlue tank replaced....

[PaulC5]

Probably the easiest and cheapest thing to do will be a few long motorway trips, 200 miles at about 10p/mile is only around £20 and if you need to go somewhere anyway it is not wasted money. Then if this does not give a fix you can then consider cleaning the dpf.

[andyandjulie]

Hi Spacebiscuit.

Get some Forte DPF cleaner (£10 each if you get a good deal), add 2 x 400ml to the tank when it's about a quarter full and give it a good drive in sport mode on the motorway for at least half an hour. I've just done this with my DS5. It will sort it out. I hate DPFs, they are a pain in the butt. I always have 2 bottles in the boot. It's been a year almost to the day since the last problem. The Forte DPF cleaner was recommended to me by an independant Citroen/DS specialist who really knows his stuff. He also recommended Shell V-Power Diesel. It works for me. Hope that helps.

Andy

[spacebiscuit]

Thanks I will give it a try. I took the car for an hour of moderate motorway driving this evening, I had the brainng error and random brief braking on the cold start but fine on the motorway, and also fine after the motorway on local roads. Problems seem evident when cold.

Also to add, at the moment the ECO mode is not selectable, seems to be disabled. I'll see if any faults clear after next cold start.

[PaulC5]

ECO mode (stop/start) is probably not working if the battery is not fully charged. Before the first start on a morning fully charged would be 12.7 volts.

[spacebiscuit]

The stop start has never worked... I think the battery is not compatible. The ECO Mode is a more economical driving mode that was working before. I have a USB charger that is showing 12.6 or 7 after startup.

[PaulC5]

12.6 or 7 after start up does not tell you how bad the battery is before start up so you need to have another look. If you do not have a smart alternator then the battery should be showing about 14.4 volts with the engine running. If a smart one then with the engine running and with the lights on and other things like the rear window heater it should also be about 14.4 volts or 15 volts if an AGM battery is standard.

The ECO mode on your car must be different to the one on our 308 which is just for the stop/start.

[spacebiscuit]

Get some Forte DPF cleaner (£10 each if you get a good deal)

Where are you buying this from?

[spacebiscuit]

I just checked the voltage - before starting 11.7v, once started 13.9v... I think I need to put it on a porper charge and monitor its behavior. A replacement likely required I expect.

[spacebiscuit]

I've ordered a new Varta AGM battery - I've been reading and apparently a lot of the sensors and detection systems are particularly sensitive and require stable voltage. Seems not only do I have the wrong battery type but a a dying one too - the cold weather of late being the beginning of the end of its life.

[andyandjulie]

Get some Forte DPF cleaner (£10 each if you get a good deal)

Where are you buying this from?

Ebay, last week £32 for 3 bottles.

[spacebiscuit]

So with the new battery things were much improved. I took the car on a motorway but it was lacking power - struggling to do 60mph and the brake and sensor warnings returned.

So I stopped the car, cleared the fault codes and added some Regex DPF cleaner to the tank. Then I drove 1hr 30mins 50-60 mph - no fault codes and perfect performance. The next day I drove the the return journey again all good. Since then mainly have been local, vehicle was serviced last week, and so far all fine with no fault codes or errors.

Hopefully this might help someone else!

[Djandree]

Hello
First do this from that topic. viewtopic.php?t=82188 I got 1.5hdi and when diode is on, just driving to finish dpf regen. Haven't got any issues with clogging at all (no fault codes or even information about clogging). I am driving mostly thru town and dpf is regenerating every 150 - 200 miles and around 300 miles when I am hitting motorway (Diode is on every time when dpf is regenerating) Second add Liqui Moly Def Anti Crystal Additive Concentrate to your adblue tank (I am adding bit of extra concentrate for a tank for safety))) ). I was trying different additives but this one looks like a solution for problem with urea injector. Is not clogged and have no fault codes involved with insufficient work of denoX system.