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Know Your Car Basics 101: Faulty Dumb Car Keys, Almost End Spending RM950!

Car Key Mercedes

Unlike car keys in the olden days, modern car keys are sensitive, high-tech with many functions, and unfortunately not cheap when it comes to getting replaced or serviced. At times, it is a nightmare as the car cannot be started without a working car key & the electronics inside. Image source: Pexel /Mike B

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Car Keys Low Battery Dashboard

I never had this message flash out in my older cars as most of the workings in the background were mechanical instead of electrical which made things less complicated. Things are totally different nowadays with modern cars. Image source: TDI Club Forum

Battery Low Indicator

It has been displaying on the dashboard but I guessed my wife did not notice it until I took her car out for a drive and the low battery message immediately appeared on the dashboard screen. Thinking that it was a misread, I checked with the other key and no such message appeared.

This meant that the battery in the first key was low and the battery in the second key was still strong. I guess this is because my wife only used the first key more often. This is why I always swap the keys every week so that the batteries degrade consistently.

Considering the time since we bought the car, it is reasonable that it is high time that we need to change the car key batteries. And I know the place to change the batteries although I know they will be changing twice or triple the price of the batteries sold online. But in the course of my daily routine, I just happen to pass by the place I changed the batteries for my watch and I decided to change the car batteries there instead.

It was a big mistake!

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To be frank, if one has the right model battery which can be bought rather cheaply online, one can change the batteries without the need to go to a locksmith or watch shop for battery replacement. 

Faulty Car Start Problem

The guy who changed my watch battery was at the shop but unfortunately, a young lady behind the counter was handling the car battery change at the watch shop. I should have sensed the problem when I noticed she looked clueless with the car keys and talked to the guy who is in the shop.

She got the right battery but something was not right when I pressed the buttons and there is no light on the car keys. Even the guy at the shop looked confused and asked if the car keys suppose to show any lights when we pressed the buttons. Thinking that the new battery that they changed is faulty, they opened the car key casing just to realize that the lady had placed the battery upside down.

The matter was resolved when she place the battery in the right way. The shop charged RM25 for each of the car key batteries and I decided to get both car key batteries replaced. I tested immediately by locking & unlocking the car with both keys just to make sure it is working right especially when the lady at the shop had placed the battery wrongly which may short-circuit the circuit board inside the key casing.

Then once we are back home, we started to have a problem with one of the keys – it can lock & unlock but when we try to start with the keyless button, nothing happens. But after several tries of locking & unlocking, it suddenly starts but once shutdown, starting was a problem again. At one point, we got stuck at a fast food restaurant for almost 30 minutes trying to get the car able to detect the key to start.

It was late in the evening & we had other engagements so I decided to go back to the watch shop the next day to check on the problematic key. In the meantime, we decided to use the other key that is working well.

Car Key Shopee Online

A full replacement of the car keys and the locks varies from one car model to another and is priced differently. A replacement for a Proton Iriz for example can cost between RM250 to RM500 depending on the replacement quality. Image source: Shopee

When RM950 Quoted

It was obvious that one of the keys had a problem but I was not sure if it was the one where the lady at the watch shop had placed the battery wrongly. I went back to the shop where I had changed the battery but the guy insist that changing the battery even upside down would not have caused the problem. It was obvious that it was no point arguing with the guy at the shop.

I head over to a locksmith nearby to get the key checked. The guy at the locksmith placed the key on some device and then called someone on the phone. It looks like this guy was not so experienced with car keys and after a while, he informed me that he thinks that the problem was due to a faulty chip inside the key circuit. It will cost about RM400 to change the chip.

I decided to get the key checked at another place as this seems too expensive and the guy seemed unsure of the actual problem. So I headed to another locksmith – the place where I actually wanted to change the batteries in the first place. The lady behind the counter took one look and asked me to go back to the car service center to get the keys checked.

All she can do now is to create new keys and which will cost about RM950 for the original set and if I want a cheaper, non-original set, it will cost about RM500. Further, if I want to change, she requires a deposit of RM100 and it will take a few days for her to order the keys.

It was not a sensible solution and it was too expensive compared to similar sets that I can buy online. I decided to wait till I was free to go to the car service center to get the key checked properly.

Final Solution

Since there is still one working car key, we had to contend with this until I get the one that is not working to be checked and serviced at the authorized car service center. Despite this, I know that eventually if the faulty car key cannot be repaired, I have to fork out at least RM500 for a new key.

Considering that it is likely that I need to get a new replacement, I decided to reopen the faulty car key casing again for one last time to check. I took out the battery and it looked in good order. Then I checked the circuit board for any abnormal signs and there was no chip that I could sight. Everything looks intact and normal. I took out the circuit board from the casing and even took out the rubber layer for the buttons.  Everything looks fine.

I reassembled the components inside the car key casing and just for one last try, I entered the car and noticed that the light on the car key triggered when I closed and opened the door. It was not there earlier. Then I noticed that the light on the push button is working when I try to start the car. To avoid it being a lucky incident, I retried a few times and the faulty car key was indeed working.

I suspected that when the lady at the watch shop must have caused some of the connection to the circuit board to be loose when she opened the key casing or when she closed the casing, it was not done right. It looks like there was something was disconnected. Now after I assembled it back and ensure all joints are well connected, the faulty car key may not be faulty after all.

Good thing I did not agree to spend the RM950 out of panic to get the new car keys. It was a small issue after all.

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