Seller Erase Error Codes before test drive?

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Wed 24 Dec 2014 16:22
Seller Erase Error Codes before test drive? - bery_451

I dont see the point of the buyer taking a diagnostic code reader to the car that he/she will view/test drive when the seller can erase the codes from the car before the buyer turns up.

Can a test drive bring the error code/s back? If not how does the buyer is sure that the car is error free before spending lots of money?

Do all Error Codes Register a orange enging light on dashboard or is there some error codes that do not show up on dahboard but instead only on the diagnostic code reader?

Is there some error codes that can never be erased that will always show up or error codes that will show up agian straight away after erasing them and starting the engine?

Thanks,

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Wed 24 Dec 2014 17:18
Seller Erase Error Codes before test drive? - craig-pd130

Depends on the age of the car, the make and model, and the nature of the fault.

For example, a slightly dodgy oxygen sensor might throw a fault code, and trigger the 'check engine' light. If it's reset, it might work fine for a couple of hundred miles before throwing a code again.

I'm not sure if any cars actually do store every fault code in the ECU, even after a reset.

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Wed 24 Dec 2014 17:20
Seller Erase Error Codes before test drive? - RT

If any error codes have been cleared, and the engine management light is off then is means the system isn't currently detecting any faults.

Many, perhaps most, faults are corrected by replacing a component, clearing the codes and seeing if the fault is corrected.

You can't expect to be able to see the fault history, or correction history, with a code reader - and it's unfair on the seller to leave codes without clearing if they've paid to correct the fault.

If there's a fault with the car at the time of the test drive, the engine management light will be on and a code/codes stored.

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Wed 24 Dec 2014 17:24
Seller Erase Error Codes before test drive? - Hamsafar

I've never known a car where the seller appears to have cleared the fault codes. When I scan there are historical faults - sometimes years old and sometimes with freezeframe mileage that is higher than that on the odometer.

It depends on the type of fault - usually only emmissions-related faults put the EML light on, things like sticking doorlocks or failing batteries just store codes.

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Wed 24 Dec 2014 17:56
Seller Erase Error Codes before test drive? - coopshere
"If not how does the buyer is sure that the car is error free before spending lots of money?"

If spending lots of money the best course of action for peace of mind is to only buy from a reputable dealer where you will have some recourse if faults do materialise.
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Wed 24 Dec 2014 18:01
Seller Erase Error Codes before test drive? - TR7
"If not how does the buyer is sure that the car is error free before spending lots of money?" If spending lots of money the best course of action for peace of mind is to only buy from a reputable dealer where you will have some recourse if faults do materialise.

Never was a truer word said

Edited by pkqpr on 24/12/2014 at 18:02

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Wed 24 Dec 2014 18:04
Seller Erase Error Codes before test drive? - bery_451

Obviously nowdays most cars are electrical computers unless your car is over 50 years old meaning its mostly mechanical and little or no electrical.

Does every code error reader have a Historical feature like you said when the seller erases the codes it still shows them? Is it like emptying the recyble bin on windows but its not really deleted off the hard drive?

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Wed 24 Dec 2014 21:50
Seller Erase Error Codes before test drive? - Wackyracer

If the seller tries to just clear error codes to sell a defective car, Then the error codes should come back when the vehicle is driven.

Some cars won't light the MIL when even there is an error, It all depends on the car in question and what the codes are. Some Fords don't bring the MIL on even if there are fault codes stored in memory.

If a person has a decent scan tool (not the usual dross sold on auction sites) then it should be able to read any stored codes or any fresh codes brought about by the test driving of a car with a fault.

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Thu 25 Dec 2014 17:56
Seller Erase Error Codes before test drive? - bery_451

Reccommend a good diagnostic code reader that can read erased codes.

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Wed 31 Dec 2014 14:52
Seller Erase Error Codes before test drive? - bery_451

Anyone?

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Wed 31 Dec 2014 15:48
Seller Erase Error Codes before test drive? - RT

Anyone?

Then there probably isn't one.

If the fault was corrected properly, ie replace the faulty part, then it's right that the code should be erased with no trace - if it wasn't correctly properly, a new fault code will show when the car is used so you'd be able to see that.

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Wed 31 Dec 2014 18:12
Seller Erase Error Codes before test drive? - elekie&a/c doctor

Some cars built within the last 5 years or so ,have the ability to store code history even if the malfunction light has been extinguished.None of the generic code readers have this facility,so you are going to need to spend around £2k + on equipt to check this.(that is per make)

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Wed 14 Jan 2015 15:58
Seller Erase Error Codes before test drive? - YG2007

Just to be clear the engine managment light (amber) MIL lamp etc can be read by an EODB device which will give you some information on the health and well being of the engine and emissions system. It wont however confirm the vehicle has no faults. A modern S class for example has up to 200 modules in the vehicle controling all aspects of the vehicle and are linked via a network system / systems. So whilst that cheap Range Rover might not have an emissions fault it may stilll have faults with the air suspension system for example that can cost lots to fix....

Engine managment light on is now an MOT failure item.

ABS light on is the same

A Code reader depending on what you have available to you will only tell you some of the story and not identify other faults with suspension, transmission, climate control etc....

Purchase a vehicle with a good warranty and if its a potential money pit (old Range Rover ) pay for a 3rd party inspection. A couple of hundred quid well spent if it allows you to walk away from a pup or leverage something off the value of the vehicle to pay for the repair or the inspection

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Thu 15 Jan 2015 13:24
Seller Erase Error Codes before test drive? - Gibbo_Wirral

I've caught a couple of home traders out in the past by hooking up my specific marque diagnostic gear (Lexia & Peugeot Planet).

On Peugeots it records the fault and the mileage it occurred, so even if the codes have been cleared and the car not driven (much) to make the fault light come on, the codes are there.

But, as has been said, cheapo generic readers won't be able to pick up these faults.

It can also light up all the lights on the dash, so its useful to see if any displays or bulbs have been deliberately covered or broken (now that bulbs are integrated into the dash circuit board some traders have been known to stick black electrical tape over them).

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Wed 28 Jan 2015 11:54
Seller Erase Error Codes before test drive? - bananastand

The first thing to do, when filtering out dodgy private car sellers before bothering to inspect the vehicle, is to ask, "is it your name on the V5?"

When they go "no because it's me dad's/I'm selling it for me mate/it belongs to x/he doesn't want you going to his house, he's not well/I just bought it and never got round to changing it"

**click** brrrrrrrrrrrr

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