Car service due. How does car know?

BBR

BBR

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Brian
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When the "car service due" comes up on the dash board how does the car know? Is it simply distance travelled, or is it a bit more scientific?
Reason I ask is I am really busy over next couple of weeks and would prefer to put service off but obviously don't want to damage car.
Its a Discovery 4 with 175000 miles done.
Thanks for your advice.
 
Yeh, the on board computer works it our from the odometer distance. You're fine to leave it for a couple of weeks.
 
I'm not sure on the discovery, but the cars never know if they have been serviced if the garage forgets to reset the ecu. So the ecu doesn't monitor the actual state, just the expected state. There car club i was in used to offer members an oil analysis service which would help.
But back to your question, I guess it depends how much mileage your are going to do over the service due time.
 
I think on our old Volvo V40 the service prompt flashed up too early, we had hardly used the car. So ours may have been on a timer of some sort, although I could be wrong.
 
Depends on how old the car is. Older cars will just be mileage or time since the service light was last reset. More modern cars, especially diesels also take into account number of starts and mileage covered. Diesels used for short journeys don't warm up properly meaning the oil can become diluted, an oil service light will come on when it feels the oil should need changing and will likely be before the rest of the car needs servicing.
There is usually an allowance of mileage and or time that you can have a vehicle serviced without affecting a warranty. Each manufacturer is likely to be different however. Chances are there will be something written in a service book regarding this.
 
boogie man said:
Ours seems to do it by date rather than mileage.
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Most service intervals are xxxxxx miles or x years, whichever comes first. I'd guess if you were doing less than the service interval mileage you're get a reminder around every year :)
 
Russ77 said:
Most service intervals are xxxxxx miles or x years, whichever comes first. I'd guess if you were doing less than the service interval mileage you're get a reminder around every year :)
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That would make sense, we don't use the car an awful lot tbh.
 
Certainly my 8-year old golf had gave a warning on when the service was due. Definitely not based on time/distance because it warned that a service was due in 1000 miles, and then next time it dropped to 50 miles despite doing only 10 miles in between. Have opted for oil change every six months.
 
boogie man said:
Ours seems to do it by date rather than mileage.
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You don't drive much then. I could do 50k in a year if I made a good effort. That's 4x oil changes.
 
My A3, now 7 years old, seems to calculate by time and millage. Currently says something like service due in 16 days or 9000 miles. Think it's actually just a brake fluid change, wish it would say what was needed but I guess they want you to ring them up to get you on the hook.
 
BBR said:
Thanks for the advice everyone:)

I will hold off for a bit.
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You certainly don't want to drive with oxidised due to age or contaminated oil. Better change than be sorry.

For some inspiration check ebay for spares and repairs. Half of the listings are due to some poor sod not changing the oil or loading incorrect spec.
 
LongLensPhotography said:
You don't drive much then. I could do 50k in a year if I made a good effort. That's 4x oil changes.
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Yeah we don't use the car a lot, probably average 9-10k a year. We're both retired so it's not used for commuting. I've got a motorbike as well.
 
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LongLensPhotography said:
You certainly don't want to drive with oxidised due to age or contaminated oil. Better change than be sorry.

For some inspiration check ebay for spares and repairs. Half of the listings are due to some poor sod not changing the oil or loading incorrect spec.
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Two weeks isn't going to make much difference.
 
Mine said it needed one 8,000 miles ago. I phoned the garage, they disagreed. It's like the rest of the lights on there - if it's red call the RAC; if not, it's probably not important.
 
Mine are all setup for variable. It depends on my driving according to the manual.

I think it is just when the dealer needs some money :)
 
I am a big fan of regular oil changes over and above manufactures specs.
our c3 1.4 petrol gets fresh oil every 10k even thugh its 18k intervals.

oil is cheap, engine repairs are not.
 
Mr Bump said:
I am a big fan of regular oil changes over and above manufactures specs.
our c3 1.4 petrol gets fresh oil every 10k even thugh its 18k intervals.

oil is cheap, engine repairs are not.
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Depends on how you use the car, lots of short trips where engine doesn't warm up properly, it is advisable. Most oils are semi or fully synthetic now and have the capability of operating well under normal conditions for long lengths of time.
 
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