BCM issue and Hyundai saying you all “think your experts”

8700 Views 24 Replies 7 Participants Last post by Red Raspberry, 9 mo ago

GeneQueen

Discussion Starter · Nov 13, 2019

So put a new starter in and I was still having the same problem of the car starting and then if I tried to immediately restart it wouldn’t. Replaced battery terminals, battery fuse, brake switch, push button switch, no fuses blown and throwing no codes, so took it to Hyundai yesterday to have them put it on diagnostics. What I thought was funny is that I have done all the work and he looked at me like I was stupid because I got help from this forum and doing my research. The Hyundai tech said “they all think their experts” talking about forums. I left and thought what a dick. They called me this morning and told me I needed a new BCM and that it was $1100 plus $200 to flash it. I made sure I asked him the BCM or ECU and he repeatedly told me BCM. What a douche I can buy one new from another Hyundai dealership for $150-$200 and have it flashed for $200 plus 1 1/2 hour labor or I can send it off and have it repaired for $225 and not have to it reflashed and a lifetime warranty at g7computers.com. Why would he think I’m stupid. LOL. Honestly I don’t even know if it is the BCM it could just be a bad ground or something. Because if I let the car sit for a little bit it starts right up and I have been able to get it to restart after shutting it off a couple of times so I think it’s a wire what do you all think and where do I start checking. There are no warning lights on, the only problem is starting and restarting and navigation screen is fading out but the rest of the car is fine?

See less See more

Save

21 - 25 of 25 Posts

Red Raspberry

· #21 · Nov 23, 2019

This must not be a Hyundai dealer if they are calling it the PCM? PCM generally is a ECU that also takes care of auto transmissions. Our cars have the TCU for the autos and an ECU for powertrain control. Yes, the Power Distribution Module controls many of the functions through solid state relays. It's on the back of the interior fuse box.

Sounds to me like they are guessing. Someone needs to get a voltmeter and do some checking when the car is not starting.

Save

GeneQueen

Discussion Starter · #22 · Nov 23, 2019

Red Raspberry said:
This must not be a Hyundai dealer if they are calling it the PCM? PCM generally is a ECU that also takes care of auto transmissions. Our cars have the TCU for the autos and an ECU for powertrain control. Yes, the Power Distribution Module controls many of the functions through solid state relays. It's on the back of the interior fuse box.

Sounds to me like they are guessing. Someone needs to get a voltmeter and do some checking when the car is not starting.

@Red Raspberry that’s what I thought. It’s a true Hyundai dealearship. LoL. Actually the service manager is the one who sent me the email because I was getting pissed that no one could answer any questions.

Save

don11995

· #23 · Nov 12, 2021

GeneQueen said:
@Red Raspberry that’s what I thought. It’s a true Hyundai dealearship. LoL. Actually the service manager is the one who sent me the email because I was getting pissed that no one could answer any questions.

I do not know if You are interested in what I say but I have mostly the same error last week. I have a Hyundai Ioniq Hybrid 2017 and last week it just stopped on the road with the "Check hybrid system" error. After that, I tried to restart the engine, but it did not start and there were no errors at all. Ok, I thought that there are some hidden errors that only GDS will see. And no, just nothing, no any errors. After that, I started to check all fuses and found that the main battery fuse was blown. I replaced it, but nothing happened - no any errors and the engine did not want to start.

Then I thought, maybe somewhere in the blocks the car remembered something wrong with the battery and just didn't want to reset it, since this was not an error for it? A stupid idea came to my mind to make additional errors and then just reset them in the GDS. I unplugged some of the motor connectors and errors started to appear in GDS. After that, I reconnected everything that I disconnected before and reset the errors. And you know what? The car started up as if nothing had happened without a single mistake. I tried to reset when there were no errors - the car had not started. Here is the feature of these cars, that I know for now=)

See less See more

Save

Reactions: 2

Gmanns

· #24 · 9 mo ago

GeneQueen said:
@shadowtrench I hope you don’t have any more problems. Your right on the intermittent BS it sucks. I don’t lose any power when starting the car. If you look at my thread I posted earlier today you will see what Hyundai says it is. I can start the car now but if I shut it off and immediately try to restart it won’t. It has to sit for 15-20 minutes or longer before it will start again. Hopefully I get it fixed. Lol

I had the same problem with a 2011 Santa Fe.
Intermittent no crank and after an hour it would start and run okay.
Fact that it runs okay led me to to conclude that the BCM is not likely bad.
I had to replace the intake so I installed a starter and found the one I removed was a NAPA starter and it wasn’t that old,but replaced it anyway to rule that out.
Car has Hyundai Autostart so I had it removed thinking that was the cause and now my key fob will not lock or unlock the car. After about a week, no crank.
I talked it over with an experienced and trained diagnostic guy and he supplied me with a schematic and I zeroed in on the 4 contact clips that the relay plugged into(under hood fuse box).
I wanted to see if the terminal coming from the ECU was providing the necessary ground to activate the relay, so I shoved a wire connector ( spade) into the slot and found that it was barely making contact. To explain it a different way, the relay would not complete the circuit because there was a bad connection to the ground pin on the relay!
I used a dental tool to bend the contact clip so there is a good connection and it’s been a month since and no problem.
Journeyman mechanics run thier diagnostics and draw thier conclusions based information they get from thier diagnostic scanners, and flow charts but it’s never easy to isolate an intermittent problem. It’s easy to simply blame a component because it it’s almost impossible to thoroughly test in a mechanic stall.
From what digging I’ve done it’s obvious that this is a common problem and I hope this helps out the DIY and pros alike.
Gordy

See less See more

Save

Reactions: 1

Red Raspberry

· #25 · 9 mo ago

Gmanns said:
I had the same problem with a 2011 Santa Fe.
Intermittent no crank and after an hour it would start and run okay.
Fact that it runs okay led me to to conclude that the BCM is not likely bad.
I had to replace the intake so I installed a starter and found the one I removed was a NAPA starter and it wasn’t that old,but replaced it anyway to rule that out.
Car has Hyundai Autostart so I had it removed thinking that was the cause and now my key fob will not lock or unlock the car. After about a week, no crank.
I talked it over with an experienced and trained diagnostic guy and he supplied me with a schematic and I zeroed in on the 4 contact clips that the relay plugged into(under hood fuse box).
I wanted to see if the terminal coming from the ECU was providing the necessary ground to activate the relay, so I shoved a wire connector ( spade) into the slot and found that it was barely making contact. To explain it a different way, the relay would not complete the circuit because there was a bad connection to the ground pin on the relay!
I used a dental tool to bend the contact clip so there is a good connection and it’s been a month since and no problem.
Journeyman mechanics run thier diagnostics and draw thier conclusions based information they get from thier diagnostic scanners, and flow charts but it’s never easy to isolate an intermittent problem. It’s easy to simply blame a component because it it’s almost impossible to thoroughly test in a mechanic stall.
From what digging I’ve done it’s obvious that this is a common problem and I hope this helps out the DIY and pros alike.
Gordy

I had the right rear taillight that was intermittent. You could wiggle the connector and get it to turn on. I finally bent the male pin just a bit so it made better contact in the female connector. Hasn't failed yet in 4 years since.

I have my high speed fan doing the loose connection in the fuse box right now. I have an LED wired into the ECU ground pin and it comes on, but if I wiggle the relay it will cut out and in.

Save

21 - 25 of 25 Posts

This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.

Top Contributors this Month