[Ashish.Dhagat]

Hello All,
My Hyundai Verna 2009 sx vtvt 1.6 model (petrol) is having a strange issue. The immobilizer light in the dashboard works fine when starting, then vehicle runs for 4-5 mins and shuts down. After that immobilizer light doesnt work and vehicle doesnt start upon ignition. If I try after 4-5 hours, it again works but only for 4-5 minutes. Any help on what this could be related to? Pics attached

[ssjr0498]

How's the battery condition of your key?

[SS-Traveller]

Could be a variety of reasons:
- water in fuel;
- clogged suction-end (bottom of tank) coarse filter;
- moisture in HT coil packs;
- shorted spark plug(s);
- immobiliser faulty / not communicating with transponder in key.

Can't arrive at a definitive diagnosis without actually seeing the car.

[Ashish.Dhagat]

Hi there,

The key battery condition seems fine. Could this a possible reason?

---------

Hi, thanks for the reply. Forgot to mention earlier, the car start issue indeed was preceded by moisture accumulating in the car for one complete night. However, wondering that shouldn't all of these cause a more permanent trouble, instead of the car starting every few fours and running for few mins before stalling again?

Regards,
Ashish

[Trojan]

It could also be due to EGR valve clogging or failure, check with OBD scanner on possible error codes, usually for EGR valve, no issue is detected as its more of a mechanical failure of the valve rather than an electronic one.
I had faced the exact same situation in my Tata Aria and it was quite tricky to diagnose.

Originally Posted by 2000rpm

A 2009 Petrol car would have an EGR??

Unlikely in my view. This seems like a sensor issue for either the key or the car detector.

Its a guess at best due to the similarity in behavior of stalling and not restarting, I am not aware whether the Verna was equipped or not, but am quite certain that some Petrol engines do have EGR.

[2000rpm]

Originally Posted by Trojan

It could also be due to EGR valve clogging or failure, check with OBD scanner on possible error codes, usually for EGR valve, no issue is detected as its more of a mechanical failure of the valve rather than an electronic one.
I had faced the exact same situation in my Tata Aria and it was quite tricky to diagnose.

A 2009 Petrol car would have an EGR??

Unlikely in my view. This seems like a sensor issue for either the key or the car detector.

[vigsom]

Originally Posted by Ashish.Dhagat

Hyundai Verna 2009 sx vtvt 1.6 model (petrol) is having a strange issue. The immobilizer light in the dashboard works fine when starting, then vehicle runs for 4-5 mins and shuts down. After that immobilizer light doesnt work and vehicle doesnt start upon ignition

I'm assuming that when you turn the ignition on (not crank), you're able to see the the following:

1. Check Engine Light(CEL) - steady
2. Immobiliser light - steady and not blinking
3. Oil pressure light, battery warning light - both steady
4. brake system light connected to handbrake and brake fluid reservoir switch - steady
5. ABS light - steady and must disappear after 2-3 seconds
6. Airbag lights - must disappear after 3-4 seconds

Both the pictures you've posted show no CEL. When the ignition is turned on

a) CEL not glowing(or glowing for a fraction of a second and immediately going off) plus
b) Immobiliser light not glowing

is most likely related to a few pins on the ECU having deposits on them, resulting in the communication going off momentarily.

Actions:

1.Perform an OBD scan (it is likely that the OBD tool won't be able to read from the ECU if there is a communication issue)
2.Check the ignition fuse located in the fuse box for improper contact
3. Inspect the main relay (not sure where this is in the Verna but will most likely be in a fuse box in the engine bay)
4. Disconnect battery negative, open ECU couplers and check if all contact points are clean on the coupler side and the ECU side

[eccentric]

Symptoms indicate a failing immobilizer fuse. Check whether the fuse of the immobilizer is in proper condition. As a preliminary troubleshooting step, try replacing it with the spare fuse of the same rating provided in the fuse box.

Originally Posted by 2000rpm

A 2009 Petrol car would have an EGR??

Yes, some petrol cars have EGR. The eight generation Civic FD has an EGR setup as seen in the picture below.

[Ashish.Dhagat]

Thanks All. Found the root cause - The IC of the ECU was damaged. So, got it replaced and working OK now. Still do not know how it got damaged. There was indeed lot of moisture in the car a day before, but that shouldn't be a reason for damaging the IC.

[SS-Traveller]

Originally Posted by Ashish.Dhagat

Thanks All. Found the root cause - The IC of the ECU was damaged. So, got it replaced and working OK now. Still do not know how it got damaged. There was indeed lot of moisture in the car a day before, but that shouldn't be a reason for damaging the IC.

How was the diagnosis arrived at? What was the DTC (fault code) generated, if any?

[Jaguar]

Originally Posted by Ashish.Dhagat

Thanks All. Found the root cause - The IC of the ECU was damaged. So, got it replaced and working OK now. Still do not know how it got damaged. There was indeed lot of moisture in the car a day before, but that shouldn't be a reason for damaging the IC.

How was it fixed? Replaced the ECU or just the IC?

[Jeroen]

Originally Posted by Ashish.Dhagat

Thanks All. Found the root cause - The IC of the ECU was damaged. So, got it replaced and working OK now. Still do not know how it got damaged. There was indeed lot of moisture in the car a day before, but that shouldn't be a reason for damaging the IC.

Sorry, I do t understand what does the IC of the ECU was damaged mean?

Jeroen

[sagarpadaki]

There is this nice video about how a damaged component in the ECU unit can cause these starting and stopping issues.

https://www.youtube.com/watch?v=NQLkilkfc-4