Disclaimer: I am not an automotive mechanic, nor do i have a deep knowledge of the Fiat Ducato under the hood which will become obvious from the following, much of the below is trial and error.
I had asked a garage to look at the error during an MOT but was told after the error was cleared it had not returned and it was suggested it may be better to check with a Fiat dealer and that it could be expensive to troubleshoot, hence, I wanted to check basics.
Vehicle Model: Swift Escape 695
Engine: Fiat Ducato 130MJT 2.3ltr
Engine Model: ZFA250000
Issue: Engine warning light showing on dash. Using a ODB2 scanner gives a P053C - "Crankcase Breather Heater - circuit high" error.
Issue gradually becomes worse:
Engine warning light initially came on whilst about 200 miles from home on the way to a camp site. I had no way to check the error at the time so had checked the fuel cap was on correctly as I had added fuel that morning. After doing this the light disappeared.
Next trip was a few weeks later and error reappeared, again thought maybe fuel cap, again removed, put back on (tried 3 times), error disappeared.
Drove a couple of miles and error reappeared. I am now thinking that fuel cap is a red herring and it may be the act of restarting.
Obtain an ODB2 scanner from Amazon, model is a RICOKEY bluetooth 4.0. This is plugged into the ODB2 port on right hand side of cab (this is for UK).
Run scan with ignition at Accessories. Error shown, cleared then engine running, no occurrence for trip.
From here, generally when starting out with engine cold, issue reappears. Then as time goes on it will show a couple of minutes later, cleared, ok until next time. Then starts coming on intermittently during trip.
Taken for MOT, keep light on so that it can be looked at, but they cleared error which then stayed off and gave the advice outlined previously.
Amateur Diagnosis carried out:
Fuses in cab and also under bonnet checked, nothing had blown.
I noted under bonnet, that fuse F04 is labelled as Exhaust Heater (i don't know if related, but did remove fuse for diagnostic step, this made no difference to engine light) and replaced.
Hindsight is amazing, but after trawling the internet, I found some information that the Crankcase Breather Valve can cause this. Diagnosis is to remove the tube and see if there is any suction, there was not, there was actually a slight positive pressure. 2nd test (actually alternative) is to remove oil cap and check for suction. There was not. I did this when cold and there seems to be a VERY slight positive pressure.
I therefore bit the bullet and replaced the Crankcase Breather Valve, a screen grab is below
*this did NOT fix the issue* oil cap test was same after this also, so hope there is not a wider issue.
But in case this does help anybody, replacement requires the removal of the top cover which is held in place by 3 clips in each corner and can be pulled of with some encouragement. The hose connected to it can be removed. If never removed before, then the factory installed hose clips simply require to prise the bent metal on the clip up to allow it to be removed, then the 10 bolts. Ensure the new part has a gasket in it before fitting to avoid issues. I used a jubilee clip to secure the hose again (also ensure the small v on the hose allignes with the breather valve case.
I highlighed above that this did not resolve in case anbody makes this error.
Replace Crankcase Heater (also known as blowback heater).
Next, after considering more closely that the error is Crankcase Valve *HEATER*, i though, yeah, maybe its the heater.
I had been advised that this can be tested using an OHM meter or testing Amperage, to be honest, the information that I found was genral and to find something specific for this model was a challenge.
I had placed the meter on the pins after disconnecting the cable (or thought i had but later found i fudged it) and got no reading either for OHMs or Amps. It is akward to get to and cleary I was not on the pins properly as I tired once removed and got a reading for OHMS that was same as a replacment part.
The heater is below cicrled in RED. Circled in BLUE is the connection. GREEN is the hose clip.
If I disconnect the heater (circled blue) i get the same OBD2 error every time even if clearing it.
So obtained replament part.
Steps:
Remove hose (circled GREEN).
I had fumbled around for a LONG time trying to work out how to get to the bottom hose to disconnect as the replacment comes with this attached, and most photos online show both attached to the heater. If you need to remove the bottom end of the hose, it looks like a nightmare to get to it, especially if it is a factory clip that would need to be prised off.
However, there are 2 tabs on the yellow ring, if pushed apart slightly then the bottom hose pops out.
Current Status
Heater was replaced and reconnected. Started engine and light did not come on (it did immediately before replacment).
Disconnected electical connection, started enginer, error immediatly returned.
Cleared error, then restarted, no error.
Ran engine for some time and tried again once cooled a few hours later and still OK.
I hesitated at posting so soon, because i still need to go on a decent drive, and will be next weekend. But quietly optimistic. I will update next week or if the issue reoccurs.
Again, this is amatuer hour in terms of under the hood work, I welcolm any feedback or correcting where needed to avoid spreading misinformation, I only posted this as I found it real challenge to find specific details for the Ducaot online (but this could be down to my own incompetances navigating around a search box).
I had purchased the online Haynes manual for Ducato, but it had no information that was of any help to aid identifying the issue or how to perform any kind of tear down or removal of these parts, just to help anybody else avoid this cost.
