Thread: Diagnostic soldiers- throwing parts in hope

Originally Posted by OffTrack

Deano, .................................................. .... My point is that this post was made into probably the only sub-forum on AULRO where there IS a consistent effort made to diagnose based on a combination reported codes, LR diagnostic flows for the fault codes, and other troubleshooting information.

So it's a bit presumptuous to lecture about "Diagnostic Soldiers" when most of the regulars in the sub-forum are doing their best to avoid that situation anyway.

cheers
Paul

Perhaps you're right Paul and the original post may have been better placed in the 'general' forum but the general point(s) made IMO are still relevant.

There would be plenty more viewers than 'expert' contributors to the technical forum and it does no harm to remind people that there is no such thing as a smart instrument. All an instrument can do is give a pre programmed output in response to it's various inputs. It can't think, way up possibilities or see a problem or it's physical symptoms.

I worked in an area where specialised diagnostic instruments were rolled out to the workforce. I was the 'expert' and trainer for a very experienced and competant workforce but it never ceased to amaze me how people could believe what an instrument 'told' them to the exclusion of common sense or their own experience or senses.

I think it's a bit harsh to categorise the OP as 'presumptuous' or 'lecturing', more the giver of a timely reminder that a good Mk.1 eyeball with a brain behind it is more important in fault diagnosis and resolution than the instruments used.

Deano

No diagnostic equipment ever will be able tell you that you have a rattly gearstick, a nail in the front left tyre, a full ash tray and a rear right wheel that needs balancing and is wearing out unevenly.

And in fact no diagnostic equipment actually does any diagnosing at all.
It is merely a tool that reports what the self diagnostic capability built into any ECU has to offer and provide.

Of course direct access to this information, and even knowledge of what is possible was once something that owners themselves had absolutely no access to, but things have steadily improved, and at least now everyone has the opportunity to access that information fairly inexpensively, regardless of how they personally choose to use and interpret it.

Some may well just part swap on the basis of this information with varying degrees of success, but that approach is not all that uncommon in dealers or many indies anyway.

Some will look further into things and do more hands on testing, using the equipment to help them learn more about their vehicles etc. but very often it's value enough for many to get equipment, even if it's just to be able to see for themself what their vehicle reports, and compare it to what others may possibly tell them.

Originally Posted by BBS Guy

It is merely a tool that reports what the self diagnostic capability built into any ECU has to offer and provide.

Of course direct access to this information, and even knowledge of what is possible was once something that owners themselves had absolutely no access to, but things have steadily improved, and at least now everyone has the opportunity to access that information fairly inexpensively, regardless of how they personally choose to use and interpret it.

Some may well just part swap on the basis of this information with varying degrees of success, but that approach is not all that uncommon in dealers or many indies anyway.

Some will look further into things and do more hands on testing, using the equipment to help them learn more about their vehicles etc. but very often it's value enough for many to get equipment, even if it's just to be able to see for themself what their vehicle reports, and compare it to what others may possibly tell them.

Colin thanks for your input, your post is exactly what I was trying to say.
Even more to the point is the Dealers swapping parts unnecessarily. The point I was making was, that throwing parts at it with nil result ,then presumption that it must be another part , and throwing that at it and still the problem is not resolved is that Customers ARE PAYING for the part once fitted. I haven't heard any stories of where the parts unnecessarily fitted are then taken off and the old working part is reinstalled and the workshop has credited back payment for putting the "Wrong" part/s in the 1st instance".
I know I would be pretty peeved if an expensive part like an electronically controlled say Auto Transmission was replaced or rebuilt and it was really only an ecu connection fault. I'm sure the mechanic would fess up and tell you and refund the money , I think not.

I have one of your units and find it a great tool to explore what's recorded on the ECU etc. and I say again it's a tool.
Regards, Mario

We had an Isuzu truck in to the dealers to diagnose a "check engine" light/power de-rate.
They charged over 10 grand for a new fuel pump and injectors(common rail motor),it was back a week later looking for the same fault.They couldnt get it to fault and did nothing.
Next time it happens they want us to call them and they will send a spannerman out.OH,they expect us to leave it where it is with the motor idleing to they get here.They are 175kms away.Key off resets the issue and its not leaving a calling card in the ECU.
Andrew

Even more to the point is the Dealers swapping parts unnecessarily. The point I was making was, that throwing parts at it with nil result ,then presumption that it must be another part , and throwing that at it and still the problem is not resolved is that Customers ARE PAYING for the part once fitted. I haven't heard any stories of where the parts unnecessarily fitted are then taken off and the old working part is reinstalled and the workshop has credited back payment for putting the "Wrong" part/s in the 1st instance".
I know I would be pretty peeved if an expensive part like an electronically controlled say Auto Transmission was replaced or rebuilt and it was really only an ecu connection fault. I'm sure the mechanic would fess up and tell you and refund the money , I think not.

I do have a no fix no fee service and will prove the part fitted is at fault.
Although I have aquired a few parts along the way where I got it wrong. But at least I can sleep at night.

One of the things I got very annoyed with when I was working at a dealer was the "technicians" asking me to order in parts that they thought might be faulty....

The technicians in turn got annoyed with me telling them to **** off back to the workshop and find out whats actually wrong!

some prime examples

A friend had 2 turbos fitted under warranty to a disco 3, cause they were both knackered, ( computer said low boost pressure ) when it happeneda third time outside warranty it came to me, I put it in low and did 5 km at 3500/4000 rpm, this cleared the carbon and the veriable vaines in the turbo closed .
result 10 mins after, no need for a new turbo

second example , my mothers car had no power and lots of blacksmoke, so she took it to the local main agents payed €50 to be told it needed €3000 for a new turbo , (computre said low boost pressure) I asked if he had felt the rotor for play, he said he did not need to , the oil was very black so it had been poorley serviced,
I changed the split intercooler hose , result € 30 for a pipe and happy mother

A td5 that would not start needed 5 new injectors, the oldones had all died, new injectors fitted and still would not start, it arrived with me when I turned over the engine I was spinning twice as fast as it should , so I tow started it and it started instantly - I changed one part ( can anybody guess and I will tell you why ) But in this occasion no fault was showing

There is no substitute for old fassioned basics, ask why or what could cause the fault
Anthony

I had the 3 amigos come on the other day, cleared the fault for RHF sensor a few times, but reappeared and stay there , today I ran diagnostics, the error related to BROKEN WIRE ,loss of signal.
I pulled the brake disc off and unplugged the sensor from the hub, no broken wires, just some metal filings stuck on the bottom of the magnet of the sensor. Cleaned them off refitted sensor and cleared the fault.

The diagnostics took me the the RHF sensor, but if I read loss of signal and Broken wire and took that as gospel , I would have gone and raided my stock pulled out a new sensor and replaced it, but by using diagnostics as a Tool and pry a bit further, it was only a clean job.