[SS-Traveller]

Yesterday. I received a somewhat frantic call from a friend in Ghaziabad, who drives a 2014 Maruti Ritz ZXi. His car had gone into limp mode - it starts but will not rev beyond ~1200 rpm. The car also had the CEL (Check Engine Light) glowing. He had taken the car to his 'trusted' friendly neighbourhood garage (FNG), who, without checking the DTC (Diagnostic Trouble Codes), advised him that the ECM itself is faulty, and will have to be taken to a specialist in Noida for repair, and will cost him Rs.4000 - because, apparently, "the Ritz has a known issue with its ECM, and needs to have the ECM repaired".

For the time being, my friend has parked the car back home without repairs, since he is travelling out of town tomorrow for an extended period, and did not want the headache of leaving the car at the FNG just in case the car did not run at all.

I am curious to know:

- Is it common for FNGs or even authorized service centres (ASC) to 'repair' the ECM for any car? What is the usual amount they quote for such repairs?

- Does the Ritz petrol (or any other car) have any known issue with its ECM that actually needs repair? If so, what is the problem, and what kind of repair is required?

- What happened if you did allow the FNG / ASC to carry out 'repairs' of the ECM? Did that solve your problem, or did some other issue crop up, requiring further repairs and expenditure?

- Big question: Is "ECM repair" a scam?

[vishy76]

This is a known issue on some of the K12 engines. You can check out the video below. The guy has also posted a similar video for the Swift 1.2. The symptoms he has stated are the exact same ones your friend is facing.

https://m.youtube.com/watch?v=-guv3ogdhXw

Repairing the ECM is an economical way since a brand new ECM would definitely cost 8-10X more. I have seen ECMs being repaired for Jettas and Passats (apart from the car shown in the video above) and the issue didn't recur after these repairs.

Repairing typically involves replacing a busted IC. Though the actual cost of the IC and labour isn't much, mechanics do have fat profit margins on these, simply because they also know the customer will still find it economical as compared to getting a new ECM altogether (and having to program it again).

To conclude, it definitely isn't a scam. Yes, an ECM failure is something that is difficult to diagnose and only a mechanic who has seen a couple or more on that specific make before will know the exact symptoms and figure it out. The rest might keep doing trial and error by replacing sensors and checking the wiring.

[greenhorn]

I would not take the term "ECM repair" at face value - a lot of FNG garages have an ECM specialist on call who has all the right tools, and anything that involves a visit from them is called an ECM repair. In this case, the Mech seems to have judged from past experience or hearsay from his field of work that this is something that is not going to end with just a scan, so probably is asking him to go visit a specialist directly

Even when my Indica had a wiring harness issue (which was diagnosed later -it manifested as a CEL which said a lot of expensive and usually reliable things were faulty) - My mechanic offered to troubleshoot it, but In his judgement said it was better if we took it to his ECM guy rather than try buying and changing things the ECM said was wrong.

The ECM guy took his time (and money) but ultimately identified it as a wiring harness loose connection issue which was a simple fix. I did not contest the estimate despite the simplicity of the fix because expertise and diagnosis was most of the cost of the fix, and it saved a lot of money compared to what the trial and error approach would have cost

[SS-Traveller]

Originally Posted by vishy76

This is a known issue on some of the K12 engines.
To conclude, it definitely isn't a scam. Yes, an ECM failure is something that is difficult to diagnose and only a mechanic who has seen a couple or more on that specific make before will know the exact symptoms and figure it out. The rest might keep doing trial and error by replacing sensors and checking the wiring.

Symptomatic empirical diagnosis, without scanning, of an ECM needing repair just because the engine is in limp mode is a strict no-no in my books. However, that is exactly what the FNG wants to do - remove the ECM from the car and take it to an ECM repairer.

Originally Posted by greenhorn

In this case, the Mech seems to have judged from past experience or hearsay from his field of work that this is something that is not going to end with just a scan, so probably is asking him to go visit a specialist directly

Even when my Indica had a wiring harness issue (which was diagnosed later -it manifested as a CEL which said a lot of expensive and usually reliable things were faulty) -
...
The ECM guy took his time (and money) but ultimately identified it as a wiring harness loose connection issue which was a simple fix.

Exactly. It can well be a minor issue that does not need any fix in the ECM. So my point is, why remove the ECM from the car on a presumption?

[greenhorn]

Originally Posted by SS-Traveller

Exactly. It can well be a minor issue that does not need any fix in the ECM. So my point is, why remove the ECM from the car on a presumption?

When I read that

the ECM itself is faulty, and will have to be taken to a specialist in Noida for repair,

I assumed it was the car that was going. Re reading it, yes, I can see it's the ECM. Maybe this mech knows something that I don't ?

[SPIKE ARRESTOR]

Originally Posted by vishy76

https://m.Youtube.com/watch?v=-guv3ogdhXw

It would have been interesting to see the guy clear the DTC (at least try) using the tool before dismantling the ECU for "repair". I find it a bit difficult to believe they actually repaired the ECU.

My previous employer is a leading supplier of automotive control units. Our warranty team used to get control units from field, marked "Steuergeraet Defekt" (Control unit defective).

And what was the defect? -- In majority of cases, control unit had registered a DTC, no hardware failure.

I hope that answers some questions.

Spike

[vaasu]

Originally Posted by vishy76

Repairing the ECM is an economical way since a brand new ECM would definitely cost 8-10X more. I have seen ECMs being repaired for Jettas and Passats (apart from the car shown in the video above) and the issue didn't recur after these repairs.

If ECM has to be replaced, it does not seem to be that expensive for Ritz. It costs 8575 on boodmo. Better than third party repairs.
https://boodmo.com/catalog/part-cont...r_con-6774709/

[vigsom]

Originally Posted by SS-Traveller

- limp mode - it starts but will not rev beyond ~1200 rpm. - CEL (Check Engine Light) glowing.
- without checking the DTC (Diagnostic Trouble Codes), advised him that the ECM itself is faulty

- Is it common for FNGs or even authorized service centres (ASC) to 'repair' the ECM for any car?

- Is "ECM repair" a scam?

- Symptomatic empirical diagnosis, without scanning, of an ECM needing repair just because the engine is in limp mode is a strict no-no in my books

Originally Posted by vishy76

Repairing the ECM is an economical way

1. In this case, it was a good decision to leave the car As-Is for now given the travel on hand. Please ask him to leave the battery negative disconnected.
2. I'd never ever touch the ECU until a proper diagnosis is done using a scan tool, reading the DTC, and then inspecting for why the error code has got generated.
3. The issue on the ECU can turn out to be a simple case of corrosion on the ECU pins, dry solder on the board or something requiring replacement of a component.
4. Costing - the actual cost of repair may actually be just ₹150, but the final cost will run into thousands due to the value chain. Typically the repair is quoted at 30-50% of the cost of a new ECU. It is a win-win anyways.
5. Scam? In some cases yes, but even if it is an actual issue with the ECU, overcharging is as outlined in point no.4

These days, like in corporates, the guiding mantra in automotive aftermarket is, "Dimaag ka paisa lena"
(charge for brains)

Originally Posted by greenhorn

In this case, the Mech seems to have judged from past experience or hearsay from his field of work

Very true greenhorn. Mechanics rely on past experience or whatever has been perceived in the automotive market to give an "immediate" view rather than dwell deep. Reason: Nobody has the time or interest to get into details.

[Tgo]

If there are physical signs of damage: broken/corroded pins, cracks/dents on the casing, water ingress, heat/burn-out marks. I would rather scrap the ECM and go for a new one.

Unfortunately it is the second type of damage, the not visible one that we often face. Dealing with a failed ECM in our Duster was a harrowing experience. We wanted an explanation from Renault how it could fail without physical damage. It is not a wear and tear part.

I spoke to ECM tuners who said they can try flashing it. Spoke to Renault who said better to go with a new one. Spoke to scrap dealers who said they can arrange but were charging half the price without guarantees and also the installation had to be taken care by us. So there were too many parties to blame without clear cut accountability if we went for the repair route.

The problem we faced was luckily described in one of the service manuals. The car was running fine 3 times (starting the engine) in a row. The 4th time it went into limp mode. And this was a problem where the internals were not interpreting the data they receive from the various sensors correctly. Since this phenomenon was initiating limp mode on the 4th cycle which was by the book, we were convinced to some extent, with the explanation for the failure.

Finally we went for a new ECM. It required some initiation to match it to the car. And the Immobilizer also needs to be in sync with the ECM which was done by Renault ASC. The car runs fine now. Replacement also provided us the assurance through 20k km and 6 year warranty on repairs/workmanship.

It was a hard pill to swallow but electronic parts like the ECM can fail too. My general understanding about ECMs is that they have a table on its memory with (healthy) reference values of all parameters that it reads (through various sensors). Values that are continuously outside the reference range show up as an error code. But like any other electronic memory, it is prone to failure of one or more of the electronic components. The storage device there can also have bad / unreadable sectors over time. Making the device malfunction. No amount or repair or flashing is going to revive a bad electronic component or memory sector.

Scam or not, Would depend on how much you trust the mechanic.

[manub22]

Originally Posted by SS-Traveller

- Is it common for FNGs or even authorized service centres (ASC) to 'repair' the ECM for any car? What is the usual amount they quote for such repairs?

No idea if it's a scam, but back in 2012 my Hyundai-i10 car ECM failed, and the car was out of warranty. Due to ECM failure, the car was vibrating and wobbling while driving.

Checked with Hyundai ASS, and came to know that 2 of the spark plugs were not getting power. Initially, they told it will need to be replaced, and as it will come from Korea the new unit will cost around 36k. On further discussion with them, they told there is a provision to get it repaired, and would cost around 6-7k. I agreed to it and they took around 2 weeks to get it fixed, never faced any issues post that.

On asking for details I came to know that they send the faulty ECMs and IC circuits to some company in Faridabad to repair.

[.HEM]

ECM can be repaired. I have sponsored a guy to get trained in ECM repairing and he completed the course and is now doing it as a business. ECM is just like a motherboard of a computer. It is also a chip level service. We can diagnose what went wrong and can rebuild the ECM with replacing the necessary chips and capacitors.

[anupam00]

Originally Posted by SS-Traveller

Yesterday. I received a somewhat frantic call from a friend in Ghaziabad, who drives a 2014 Maruti Ritz ZXi. His car had gone into limp mode - it starts but will not rev beyond ~1200 rpm. The car also had the CEL (Check Engine Light) glowing. He had taken the car to his 'trusted' friendly neighbourhood garage (FNG), who, without checking the DTC (Diagnostic Trouble Codes), advised him that the ECM itself is faulty, and will have to be taken to a specialist in Noida for repair, and will cost him Rs.4000 - because, apparently, "the Ritz has a known issue with its ECM, and needs to have the ECM repaired".

Dear SS Sir,

Yes its possible to repair the ECM,

Here is my experience on few case seen so far with friends cars,

Challenges:

1. ECM Repair - complete instruments like spectrum analyser etc -have not seen in an of the repair shop, since I have had experience in the field of electronics - normally the ecm is similar to any TV PCB - which has Smt components and pcb lines - for which In case of any faulty - the first was would be to check continuity,drysolder and followed by individual Smt components and the various current which should come on pin etc,

Unfortunately since TV market is all elapsed a good electrical person who has all the instruments and is knowledge is little tough to find,

2. At the same time cases where ecm is cheaper say maruti etc - a person may change it altogether,

3. Cars in which ECM is costly - one may go in for repair - yes have seen Skoda Laura - petrol ecm getting repaired and car is up & running

4. Moreover the difficulty in such cases are ecm repair takes lot of time and with current way of working - the issue is sometime a person is very impatient,

5. I personally feel its a very good market of repair of ecm,bcm and other electronic components just that currently have not seen a setup which can do all,

Advantages

1. An ecm repair can cost you any where from 6500 rs to 30k - yes depending on car and issue and yes sometimes in case of expensive car a person might even be ready to spend more

In a nut Sheel - yes ECM is repairable and yes people are doing it.

At the same time for cars which have ECM just beneath the windshield like Skoda Superb petrol,BMW X1 - please get frabrication done to save it against dust and water - as we all know how Indian weather is,

I got it done for my cars,

I hope value is added in your post sir,

Have a wonderful day ahead,

Thanks & Regards

[ObsessedByFIAT]

Experience aside, I am still wondering how can the FNG guy be sure sure of an ECM failure? There are so many things within the engine which can cause the car to go in limp mode.

Had I been in your friends place, I would insist on getting the proper DTC code from an authorised service center before touching the ECM.

[Jeroen]

Originally Posted by SPIKE ARRESTOR

My previous employer is a leading supplier of automotive control units. Our warranty team used to get control units from field, marked "Steuergeraet Defekt" (Control unit defective).

And what was the defect? -- In majority of cases, control unit had registered a DTC, no hardware failure.

It is very common that ECUs get replaced for no reason at all. Have a look on what is says on the Jaguar Advanced Electronic Course materials:



The 80% is derived from the ECUs that have been swapped and returned to Jaguar for statistical analysis.

Obviously, if you have a faulty ECU and swap it for a new one, properly programmed, it is going to work fine. However, it also means that 80 out of a 100 Jaguar ECUs are replaced for no good reason. Jaguar mechanics tend to be reasonable trained, but they still get it wrong. Rip and replace tends to be the easy way out.

Jeroen

[vaasu]

Originally Posted by vishy76

This is a known issue on some of the K12 engines. You can check out the video below. The guy has also posted a similar video for the Swift 1.2. The symptoms he has stated are the exact same ones your friend is facing.

When I replied earlier about Ritz ECM cost, commenting that it is not that expensive, I was not expecting myself to be posting about ECM issue on my car (first generation Ritz Zxi) in next few days

So, the problem started one fine day when engine rpm started fluctuating suddenly as if one of the cylinder is misfiring. Further diagnosis at Nexa workshop using SDT revealed DTC P0102 (Mass Air Flow Circuit Low). Service advisor, without even checking the MAF sensor, declared that MAF sensor as faulty!

They did not had the part in stock. Luckily they had another Ritz petrol (used as customer drop car) and we insisted that they do a part swap and confirm if MAF sensor is indeed faulty. MAF sensor swap did not solve the problem, so they started investigating wiring issue. Post spending one full day, they could not identify the problem.

We suggested doing ECM swap as well since SDT showed either MAF sensor or ECM as potential source of problem. Swapping the ECM solved the problem! 2 full days were spent in overall diagnosis.

Have placed an order for new ECM and waiting for it to arrive.

PS: One of my friend also had to replace ECM on his Swift (using the same first generation K12 engine) for a similar issue. So, first generation K12 ECM seem to be more prone to this issue.