Rat damage to my Rapid & ECM damaged; Insurance blames dealer

am now feeling that Skoda has messed up my ECM and trying to push the bill on the insurance or me (whoever is willing to bite the bullet).

BHPian SedanGuy recently shared this with other enthusiasts.

I own a 2021 Skoda Rapid Ambition 1.0L TSI. Due to covid lockdown and my family going through covid, my car was parked in our closed garage for over 45 days. Post the lockdown and covid recovery, I decided to take the car for a spin and get it washed. As soon as I took my car out of the garage, I saw EPC light and check engine light come on. The car also started to stall after 2000 RPM. I had driven the car 100 metres or so. I brought back the car and parked it. Upon some exploration of the engine bay, I could see some rat droppings and wires chewed up.

I decided to call roadside assistance and get the vehicle towed. Please note, I drove my car for about 200 metres in total when i noticed the issue and drove it for another 10 metres or so when the tow truck arrived. The 10 m were basically pulling the car out of our garage and aligning it with truck to wench it.

At the workshop after they did the diagnosis, they said they need to replace 2 wiring harnesses and it would cost roughly 3.6k. Also after they replace the wiring, the service advisor told that they will clear the fault codes and check again. When they replaced the wires, I got a call from service advisor saying the ECM is showing as failure. The advisor said that ECM has to be replaced and it will cost 81k with labor. He also said he will try and get an insurance claim done on it.

Now fast forward after 15 days of towing my vehicle to Skoda workshop, I got a call from insurer saying that rat bite damage is not covered but they will discuss my case further and let me know.

Here are my questions to members here:

1. How can a rat bite lead to ECM failure? Isnt there a fuse which shorts out even before it gets to the ECM. Apparently the service advisor said there is no fuse to the ECM, which I find it hard to believe.

2. Does comprehensive Insurance cover rat bite? I bought insurance from Skoda themselves as I didn't want to sour my relationship with them over a few grand.

At this point, I am really confused as to what should be my next steps.

As a reference, I have highlighted the wires that were replaced. As you can see, the ECM is on the right hand side and the wires replaced are from the left hand side. There were no rat bites or damage on the ECM itself.

Update

The insurance company has refused the claim stating the following reasons:

1. The vehicle has already had wiring replaced before the claim was initiated, the insurer should have been notified when the vehicle was towed into the workshop.

2. As per the surveyor's comments, the wiring replacement work done has shorted the ECM and not the initial rat bite. The fault lies with the workshop (the insurance company said it will not be able give this in writing).

As per these above points, I am now feeling that Skoda has messed up my ECM and trying to push the bill on the insurance or me (whoever is willing to bite the bullet). I am now extremely worried and not sure what to do.

Here's what BHPian venkyhere had to say on the matter:

(1) Rat bites lead to "open" circuits, 99% of the time. A rat has to bite two wires at once to short them, and get electrocuted in the process, to cause a short.

(2) Assume that a robust rat bit two wires coming out of the ECU simultaneously and caused a short, and survived the shorting current (you didn't find a dead rat, did you?) - even then, one of the input fuses to the ECU should blow, and not the ECU itself.

(3) An ECU will "blow" only if someone makes the wrong connection (providing 12V into a slot designated for GND/signal pin OR providing GND into a slot designated for a 12V supply pin OR a cascade of mistakes where one of the two above is done in concurrence with providing a raw 12V supply instead of a designated fused supply to one of the input supply pins) and switches on the power to it. The word "blow" refers to damage to internal circuits. This is different from the term "bricking" an ECU which is software code corruption which cannot be reversed.

The point I am making, is that unless there is a catastrophic human error whilst refitting fresh warning harnesses, an ECU simply can't "blow" - its a component with a lot of overcurrent and ESD protection built into it, along with multiple fused supplies of the battery going in.

Think of it this way - rat bites damaging wiring harness is very very common in India, across brands and across locations, what happens mostly as "repair" is replacing/repairing wiring and if needed, replacing blown fuses. That's it. For the frequency with which rats bite car wires, if indeed ECU getting blown was a realistic occurence, we would have already heard of thousands of cases like this within this forum itself.

Here's what BHPian Turbanator had to say on the matter:

OP will have to involve the Skoda and hope they accept the claim due to negligence on the dealership part.

Passing the blame to customer is where VW Group dealers excel. This should have been sorted out between the dealer and company. Asking monies from Insurance/ Customer is completely unethical. This will be approved ultimately by Skoda but how many customers are aware of such technicalities or access to forums like ours? Why can't the dealership simply agree to their fault and settle internally with Skoda?

I had an issue on my 7 Series couple of years ago where I was trying to get Apple CarPlay done via an installer. For some reasons, it didn't work, and the system hanged. Despite everything, dealership could not revive, and I was looking at a large damage. But they got it covered under goodwill or whatever and a new controller was shipped from Germany with no charge to me. BMW lost a few thousand or a lac that day for no fault of theirs, but they would have earned multiple times over from me as a repeat customer.

Here's what BHPian ruzbehxyz had to say on the matter:\

This is absolutely the case. Rat bite cannot damage the ECU. Never heard of it. Even if all the wires inside are damaged, it cannot damage the ECU.

Two probable conclusions here:

1. The ASC has messed up with the wiring, leading to ECU damage. If the ECU was damaged, your vehicle would not have run when you started it for the first time. It means the damage happened at the service center, if at all it happened.

2. The ASC wants to make some more money, whether from you or the insurance company.

Here's what BHPian nagr22 had to say on the matter:

I disagree with everyone who is claiming rat bite cannot damage ECM. In order to damage any electronics, it is not necessary that its power line must be shorted. Depending on the design, even shorting an ultra low power sensor wire to ground can cause some sensitive internal component to go bust which could make the entire ECM useless. The rat wouldn't even feel a pinch when it bit some low voltage wire and might have caused it to touch the ground and an IC inside the ECM can go bust without even a tiny hiss.

Having said that, there is no way to 100% determine whether the rat damaged it or the dealership damaged it. Sad to say this but insurance company can legally wash off their responsibilities because some repairs were performed before informing them.

The best way forward is to amicably work with the dealership and see if they can push the insurance company to accept the claim. This might work if the insurance was purchased from dealer and he can use his pressure tactics. If the insurance company is adamant about not covering, try to ask the dealership whether they will cover some portion of the replacement cost as goodwill and take whatever they offer. This way you can continue to have a good relationship with the dealer for your future services.

There is a 3rd option - find an electronics technician who can repair the ECU. It's a very long shot but if the damage is to some simple resistor or a common IC, it should be a simple job of replacing it. But the technician should really know his trade to pull this off. You didn't mention what error is the car throwing which made the dealership say ECM conked off? Is it some error code or is the ECM not powering at all? If its some error code, the ECM should be repairable by a competent hand.

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