Pug 307cc non-starter

[Expertamateur]

Here we go again with the troublesome 307. Due to my limited confidence in the thing getting me home I haven't been using it much. Only short journeys maybe once a week or so. The last expense was a transporter to the nearest trustworthy garage to fit a new MAF thingie (?). Looks like a big single choke carb with a box of electronics stuck to the side of it.
Now after less than about 100 miles it won't start. The "engine" light is lit up and the starter doesn't turn. I just get a beep. I plugged in my useless OBD2 gadget and it shows P0597 Thermostat Heater Control Circuit / Open. What has this got to do with not starting? Anyway, I wondered if a low battery could be confusing things so checked with my new €65 multimeter. Only 10.9 volts. That is bad. I connected my smart(ish) charger on it for a few hours and it was still trying to pump some life into it. It started out gently and had increased to 15 volts/3amps when I decided to disconnect it and try again. Battery now showing 12.5 volts. I know that's only borderline but maybe enough. Still the same result. Turn the key and no starter. Just the "engine" symbol and a beep. Tried the OBD2 and it showed the same fault code.

I accept it is probably in need of a new battery and I'm prepared to do that but is this normal that a heater fault can prevent it starting? A couple of online fault lists say something about a clogged DPF filter which gives symptoms of excessive fuel consumption. I must say this heap certainly eats fuel. I've had better mpg out of a V8. Any opinions? I don't know whether to scrap it or throw even more money at it.

[mickthemaverick]

What year, engine and gearbox is the car? Info needed to find the correct diagrams

[Expertamateur]

Sorry. March 2006, 2litre petrol (143hp) 5 speed manual UK spec.

[mickthemaverick]

You might find some clues in this link: https://carscounsel.com/p0597-code/

[Expertamateur]

Yes. Thanks for that. I have already investigated about a dozen similar sites that give similar advice. One thing mentioned in the link was it can cause excessive fuel consumption. That seems to fit very well. It goes like stink but really gulps petrol doing it. Similar rate to a 427 Stingray I used to own.

Trouble is I wouldn't know where to find the heater thermostat and what it looks like when it fails. I guess I'm still faced with the problem of whether this car is worth wasting more money on at a garage. With so much complexity that one fault affects so many other things it looks like its not worth pursuing. It will cost me €100 to get it transported to a garage before the costs kick in big time.

[Huskyxantia]

A dpf is diesel particulate filter . So yours won't have one , if its thermostat here's a few videos to digest

[Huskyxantia]

[Huskyxantia]

[Expertamateur]

Thanks for the video clips. After much fuddling around yesterday I decided that a new battery is on the cards. After leaving it on charge all day yesterday and "resting" all night it only measures 12.04 volts this morning. So it is not achieveing and holding a full charge. After searching through all the info I could find I couldn't identify anything that might be described as a heater controller so at a guess I will try renewing the coolant temperature sender. In my experience this only sends info to the temperature guage or warning light but that has been on older cars. Today it could be sending information to some critical box of elektronikermachinen. Since it is not an expensive item and easier to get at than in the ones in the linked videos I will roll the dice. Part ordered. I will update here when it arrives. Maybe mid-next week Parts are hard to get here beyond the edge of the universe.

[Expertamateur]

It has been suggested that there is another component that could be in play. The engine thermostat is supposedly heated electrically and somehow works in harmony with the ECU. I don't really know because my fairly in-depth experience over the last 60+ years has been with technology between 1928 and 2000. I will try a new thermostat next. Spin the wheel.

Yet another rainy day so I can't get under the lid to do anything without soaking all the wonderful electronic rubbish with rainwater. Wind is blowing like mad today so not even a chance of covering the area.

[Huskyxantia]

Fingers cross for some better weather and a repair that works out for you