Last night on my way home, the glow plug light began to flash steadily (1 sec on/ 1 sec off) and the exhaust inspection system warning light came on steady.  No loss of power, the car appeared to drive normally.  

 

Recently the stop/start had been inactive for a few weeks so I took the battery out and charged it overnight with a smart charger.  Put it back in this morning and started the car.  It was very lumpy on idle and felt like a cylinder maybe wasn’t firing.  I turned it off, waited a few minutes and tried again.  It took a few cranks longer, maybe 1.5 seconds instead of the usual instantaneous start, and ran normally but still with the two warning lights mentioned at the start.  (I don’t think this charging of the battery is anything to do with the faults but I’m including it for completeness.)

 

I borrowed an OBD reader and it reports fault codes P0321 and P0697.

 

Not being a mechanic, I have no idea how significant these are so I’d be grateful for some advice.

 

I called the dealer who services it and they said to take for a good run at 50mph+ for at least ten minutes to clear the DPF but I’m not convinced that’s the problem.

 

Car is regularly serviced and has 86,000 miles.

http://wiki.ross-tech.com/wiki/index.php/16705/P0321/000801

 

The other fault is indicative of a wiring fault in the engine bay somewhere, taken in conjunction with the above this is suggestive of a partial wiring loom failure to the crank position sensor and a simple bypass cable on the 5V line should effect a simple repair.

 

Try a mobile auto electrician if this sounds like aggro to you.

39 minutes ago, sepulchrave said:

http://wiki.ross-tech.com/wiki/index.php/16705/P0321/000801

 

The other fault is indicative of a wiring fault in the engine bay somewhere, taken in conjunction with the above this is suggestive of a partial wiring loom failure to the crank position sensor and a simple bypass cable on the 5V line should effect a simple repair.

 

Try a mobile auto electrician if this sounds like aggro to you.

 

Thanks for that.  It does sound beyond my skills so I’ll leave that to a professional.

 

I’m just back from the suggested motorway run of 16 miles at 60-70mph and on the out run it was definitely sluggish, very slow to accelerate through the gears, so I guess was in limp mode.  Before the return trip I switched it off for a minute before rejoining the motorway and the glow plug light did not come back on but the exhaust inspection system light remained.  The car was no longer in limp mode and drove as normal.  Back at home, I switched it off and checked the fault codes again with the OBD reader; the same two faults were listed.

 

I started the car again and it fired up well with no warning lights showing.

 

Is it still worth getting the dealer to diagnose the two recorded faults?

 

P.S. The only symptom I forgot to mention was that since all this started is that the cruise control function can’t be set.  Don’t know if that matters.

Just using a smart charger overnight might not have been enough to fully recharge a battery that might have been low for a few weeks, did the charger show that the battery was full, if not even a 50 mile drive including 16 miles of motorway may not be enough to fully recharge the battery.  Put the smart battery charger on for as long as possible or until it shows full.

 

You may also need to keep an eye on the battery and give preventative rechargers with the smart charger before any warning lights or messages come on, or possibly need to replace the battery at some point sooner than expected.  

 

A 50 mile drive including 16 miles of motorway at 60-70mph may not be enough to fully clear the car out, especially if you were in top gear at that time and just cruising, consult your Owner's Manual to see if it gives any suggestions or go on the same drive but have the engine revs up a bit by using lower gear(s), you're looking to get the exhaust temperature up for long enough, and more air in, through and out of the engine.

 

Not sure about the cruise control but I'd fully charge the battery, go on the blow-through, heat up run, then check for error codes and decide from there if I thought it was worth going to the Dealership.

 

Personally if I had a diesel I'd check, change/clean as require, the engine air filter more often than the service schedule has it and run with something like V-Power diesel at least every fourth or more tankful.

  

 

3 hours ago, harry vederci said:

 

I borrowed an OBD reader and it reports fault codes P0321 and P0697.

 

 What make of reader was it, generic ones may not give a correct answer to issues. Suggest you try and use something VAG specific such as VCDS, user map on here, which may then indicate if it actually is linked to a DPF issue, codes do not appear to indicate this and light on dash may be a consequence of other issues.

56 minutes ago, nta16 said:

 or go on the same drive but have the engine revs up a bit by using lower gear(s), you're looking to get the exhaust temperature up for long enough, and more air in, through and out of the engine.

 

 You do not need to "have the engine revs up a bit" unless this is seen as an Italian Tune Up - the engine will either inject more fuel or change injection timing/duration - on mine (1.4TDI not 1.2TDI) the exhaust temperature as read through VCDS is dramatically raised when on a forced regen and the engine takes on a totally different sound. Below link suggests parameters when doing a forced regen that may assist if it is trying to do a self actuated regen. 

Diesel Particle Filter Emergency Regeneration - Ross-Tech Wiki

1 hour ago, nta16 said:

Just using a smart charger overnight might not have been enough to fully recharge a battery that might have been low for a few weeks, did the charger show that the battery was full, if not even a 50 mile drive including 16 miles of motorway may not be enough to fully recharge the battery.  Put the smart battery charger on for as long as possible or until it shows full.

 

You may also need to keep an eye on the battery and give preventative rechargers with the smart charger before any warning lights or messages come on, or possibly need to replace the battery at some point sooner than expected.  

 

A 50 mile drive including 16 miles of motorway at 60-70mph may not be enough to fully clear the car out, especially if you were in top gear at that time and just cruising, consult your Owner's Manual to see if it gives any suggestions or go on the same drive but have the engine revs up a bit by using lower gear(s), you're looking to get the exhaust temperature up for long enough, and more air in, through and out of the engine.

 

Not sure about the cruise control but I'd fully charge the battery, go on the blow-through, heat up run, then check for error codes and decide from there if I thought it was worth going to the Dealership.

 

Personally if I had a diesel I'd check, change/clean as require, the engine air filter more often than the service schedule has it and run with something like V-Power diesel at least every fourth or more tankful.

  

 

 

The battery was showing 12.5V on the meter yesterday, before I put it on charge.  The charger showed similar voltage initially then rapidly went up to 14.7V with just one bar (of about ten) flashing to show it didn’t need much more.  I left it on overnight anyway and at disconnection, 16 hours later, it was showing fully charged.  The battery is an E39 Varta Start-Stop Plus 096 AGM 12V 70Ah (570901076) which I fitted in July 2019 after the original gave up.

 

The car had had a good run both on Friday and Saturday when I made a trip to Fort William and back (around 120 miles each way).

 

I’ll look at replacing the air filter as you suggest.

@harry vederci sorry, you're ahead of many with the battery, it's state of charge and charging the battery with a charger, and not thinking a 20-mile journey is a long run.

 

As has been put a generic code reader might not be too accurate but if the error codes have gone it done it's job if not too accurately.  Also as put always bear in mind there can be more than one issue and/or cause(s) of issues(s).  Error codes should only be taken as possible pointers in the diagnostics process, a good scan might be pointing at the cause or just blaming the messenger. 

 

A 120 miles run is a good run but not always a good blow -out (or through) run but you'd know what it was like, I've done choking runs and smooth flowing empty roads runs in Scotland and England.

 

My wife had a 2008 GM diesel before the Fabia and the few times I drove it and very few times filled it with fuel I put V-Power diesel in and could see the evidence of the different in the rear view mirrors, I know others don't accept this for various reasons, often monetary as with my wife.

 

Until you have a new filter to compare with it can be difficult to see how dirty an existing air filter can be, I'd also wipe out the inside of the filter box and trunking as much as sensible and possible.

 

If any codes return as has already been put it could be wiring or connections, a higher level scan tool make give you more information about this but sometimes just using your own personal diagnostic tools of your human senses and mind can do more and better so always worth a look-see, especially whilst doing things like changing the air filter, look before and after doing the job.

 

What year is your car, perhaps there might be something about why the the cruise control function can't be set at the moment.

 

Edited 13 March, 20233 yr by nta16

2 hours ago, nta16 said:

Just using a smart charger overnight might not have been enough to fully recharge a battery that might have been low for a few weeks, did the charger show that the battery was full, if not even a 50 mile drive including 16 miles of motorway may not be enough to fully recharge the battery.

 

That is completely and utterly incorrect, I recently posted the worst case scenario calculations for the smallest alternator fitted to our vehicles (90 amp) for recharging after a cold start with pre and post combustion glowplug activation and even at idle the recharge time was measured in seconds, it would be recharged before you even got out of your driveway let alone 50 miles.

 

Another contributor was inspired to test his vehicle which had been left for a long period and was at 60% SOC, he did so monitoring the charge rate using VCDS, it did not even use 1/3 of the alternators output and had recharged the battery in 3 minutes, once again at tickover without even turning a wheel.

 

You have got to stop trotting out stuff that has not been relevant since the 1960's when vehicles had 22 amp (maybe less) dynamos that did not charge below the regulator cut in point and with Lucas Prince of Darkness electrics.

4 hours ago, nta16 said:

What year is your car, perhaps there might be something about why the the cruise control function can't be set at the moment.

 

It’s a 2011 (61 plate) Greenline that I’ve owned from new.

 

Funnily enough, the cruise control and the start/stop were all working normally again when I was out again in the car tonight.

I was going to look at the Owner's Manual for anything about the cruise control but if it's working now.  If both the cruise control and the start/stop are working again (they might be related, my wife's Fabia doesn't have it so I don't know how it relates to battery, start/stop if at all) and you know the battery was in good state of charge and health then did you also check that the battery post connections and main earths are all clean at (inside) connections and secure, also start/stop connector on negative clamp.  As suggested connections and wires could be checked, disconnecting and if required cleaning the connector, sometimes a spray of electric contact cleaner can be enough to clean things (or even just the disconnecting and reconnecting) and you can look at the wires for any scuffing or frailty.

 

Once had the embarrassment of a mate having to call out the services as his new model at the time 18-month old V8 Land Rover Discovery wouldn't start, the" very nice man" just took the battery post clamps off and there was a tiny spec of crud that needed cleaning off and then the car fired up like a good 'un.

 

Perhaps even disconnecting and reconnecting the battery might have been enough if the electric issues have now gone but don't bank on it straight away.

 

Forgot to put, generally Dealers wont diagnosis error codes that have been cleared and don't show up on their scanners, the first thing is (or should be) to check that the reported issues exists, no codes, and like my wife, they won't believe what they don't see wit their own eyes.

 

See how your car goes over the next couple of reasonable journeys and let us know.  If it's not against your nature or upbringing try a couple of tankfuls of V-Power, the economy needs the revenues.

 

Edited 13 March, 20233 yr by nta16