Hoondai_Ghetogen
New member
- Joined
- Oct 1, 2018
- Messages
- 1
- Reaction score
- 0
- Points
- 1
- Location
- Hotlanta, GA
- Genesis Model Type
- 1G Genesis Sedan (2009-2014)
There's two points to me writing all the stuff below my two questions/comments:
1> I hope others see and learn from my experience that it's VERY possible for something as small and seemingly insignificant to cause SO much wasted time and money. Issues that just don't makes sense when testing checks out? Don't wait as long as I did to suspect the ECU. If I'd caught this months ago. I may not have had to replace the ECU.
2> I need help with ECU replacement. From the service manual procedures I've read I should be able to replace the ECU with a flashed used unit, set the immobilizer and ECU to a neutral setting with the scantool and viola!, good as new. Why do I want to do this instead of a new one? Used:90 bucks. New: A grand.
Problem is that the first Hyundai dealership tech I tried to have it done though agreed that it could be done, but then dumped it back on me saying he couldn't get the immobilizer and ECU to talk and reset. I think he missed the neutral setting step, but I don't want to insist and then look like a dumba$$ when it's really not possible. Can anyone please confirm if it is possible, and can point me the right direction(s)?
OK. I'll try to keep a very long story brief. About 5 months ago, on a hot Atlanta afternoon in May, I go WOT to merge, and about 1 second later, total power loss. Still running, but limp mode. Pull off, shut down, wait a min, start back up. Starts and runs fine, but still limp. Shut it down again. Start up, check and clear the codes P0121, P0221 and P2119. Car runs fine for the next 3 months.
Then, 2 months ago, same codes, same circumstance. OK. Maybe somethings wrong with my throttle, or the pedal, or the wiring/ground. (Not even THINKING about the ECU at this point).
I test connections for continuity, ground, voltage leak. All good. I check throttle motor resistance, 1.9 ohms, out of spec by 0.1 ohms. (1.4-1.8 ohm tolerance) Pop open the 'non serviceable' (very easy to service) sensor and motor on the throttle body. Clean it, wear looks normal, Motor brushes look a little dark, but not terrible, and plenty of wear life left. Clean it, button it back up, 1.6 ohms. OK.... clear codes and all seems good for a week.
Does it again! Test again. Everything is in spec. WTH!? OK. Now shooting in the dark, maybe random voltage spikes that are freaking the ECM out? So I go to accessory II mode (engine off) and log throttle and pedal sensors on my OBD. No sensor spikes. Can't figure it out... so I play parts darts. (STILL not even thinking about the ECU)
I replace the pedal with a used one from a 2011 with 18k before a wreck (exact same assembly/Hella sensor). It's 50 buck on E bay. Clear codes, and within a couple days... again. Check the whole circut again, throttle resistance again, 2.0 ohms. (looking back I don't think this had anything to do with it. I tested it while the engine was HOT from a day of driving. and resistance increases with heat, etc) So I replace that with a 485$ BRAND NEW ORIGINAL BOSCH part from Korea. Clear codes. Runs great for about 2 weeks.
Then, about 3 weeks ago, all hell breaks loose. I get a P0151 Voltage low on O2 sensor bank 2 sensor 1. ?!!?!? Clear it. 2 days later it comes back. OK... I'll replace it. It's 10 years old. only 70k, but possible. Before I can, back comes... P0121, P0221 and P2119 AGAIN. HOW?! I've replaced everything already. THEN about 2 weeks ago, I get P0300 misfires, P0340 and others. But my engine runs perfectly fine. Clear codes, last for a day, They ALL come back. Then it hits me. There's NO WAY all of this is happening all of a sudden. One or two, sure, but all this, all at once, no way. Not when my engine runs just fine...
Then it hits me. It HAS to be the ECU. It's the only explanation. If my harness was melting, clearing codes wouldn't bring everything back to life like normal for a while. I'd have voltage leaks, shorts to ground, blown fuses all over the place, codes would reappear instantly, and my engine would run like $hite.
So. I rip into the ECU, and low and behold, (see pic below) one of the two capacitors on the board has puked all over the PCB, crossing about 8 traces straight from the harness to the ECU. (see the pic below, sorry it's blurry). It's eaten through the surface layer and is crossing signals from all those sensors to the processor. The other one is starting to leak too.
My heart sinks when I see the greenish/blue long line after cleaning and letting it sit while I ordered replacement capacitors. That means it's eaten all the way through the surface coating to the copper, and oxidized it. Maybe the rest are burned a bit, but those two are likely beyond my ability to repair. (I could repair large traces with solder, but these are TINY)
I solder on new caps, clean the surface a bit more, spray liquid electrical tape on the surface to prevent further oxidization, button it up and pray.
Two days without any codes.... and then today... P0152 came on. Nothing else at this point, but I believe I caught the issue too late. Those traces are fried. I now have to replace the ECU.
1> I hope others see and learn from my experience that it's VERY possible for something as small and seemingly insignificant to cause SO much wasted time and money. Issues that just don't makes sense when testing checks out? Don't wait as long as I did to suspect the ECU. If I'd caught this months ago. I may not have had to replace the ECU.
2> I need help with ECU replacement. From the service manual procedures I've read I should be able to replace the ECU with a flashed used unit, set the immobilizer and ECU to a neutral setting with the scantool and viola!, good as new. Why do I want to do this instead of a new one? Used:90 bucks. New: A grand.
Problem is that the first Hyundai dealership tech I tried to have it done though agreed that it could be done, but then dumped it back on me saying he couldn't get the immobilizer and ECU to talk and reset. I think he missed the neutral setting step, but I don't want to insist and then look like a dumba$$ when it's really not possible. Can anyone please confirm if it is possible, and can point me the right direction(s)?
OK. I'll try to keep a very long story brief. About 5 months ago, on a hot Atlanta afternoon in May, I go WOT to merge, and about 1 second later, total power loss. Still running, but limp mode. Pull off, shut down, wait a min, start back up. Starts and runs fine, but still limp. Shut it down again. Start up, check and clear the codes P0121, P0221 and P2119. Car runs fine for the next 3 months.
Then, 2 months ago, same codes, same circumstance. OK. Maybe somethings wrong with my throttle, or the pedal, or the wiring/ground. (Not even THINKING about the ECU at this point).
I test connections for continuity, ground, voltage leak. All good. I check throttle motor resistance, 1.9 ohms, out of spec by 0.1 ohms. (1.4-1.8 ohm tolerance) Pop open the 'non serviceable' (very easy to service) sensor and motor on the throttle body. Clean it, wear looks normal, Motor brushes look a little dark, but not terrible, and plenty of wear life left. Clean it, button it back up, 1.6 ohms. OK.... clear codes and all seems good for a week.
Does it again! Test again. Everything is in spec. WTH!? OK. Now shooting in the dark, maybe random voltage spikes that are freaking the ECM out? So I go to accessory II mode (engine off) and log throttle and pedal sensors on my OBD. No sensor spikes. Can't figure it out... so I play parts darts. (STILL not even thinking about the ECU)
I replace the pedal with a used one from a 2011 with 18k before a wreck (exact same assembly/Hella sensor). It's 50 buck on E bay. Clear codes, and within a couple days... again. Check the whole circut again, throttle resistance again, 2.0 ohms. (looking back I don't think this had anything to do with it. I tested it while the engine was HOT from a day of driving. and resistance increases with heat, etc) So I replace that with a 485$ BRAND NEW ORIGINAL BOSCH part from Korea. Clear codes. Runs great for about 2 weeks.
Then, about 3 weeks ago, all hell breaks loose. I get a P0151 Voltage low on O2 sensor bank 2 sensor 1. ?!!?!? Clear it. 2 days later it comes back. OK... I'll replace it. It's 10 years old. only 70k, but possible. Before I can, back comes... P0121, P0221 and P2119 AGAIN. HOW?! I've replaced everything already. THEN about 2 weeks ago, I get P0300 misfires, P0340 and others. But my engine runs perfectly fine. Clear codes, last for a day, They ALL come back. Then it hits me. There's NO WAY all of this is happening all of a sudden. One or two, sure, but all this, all at once, no way. Not when my engine runs just fine...
Then it hits me. It HAS to be the ECU. It's the only explanation. If my harness was melting, clearing codes wouldn't bring everything back to life like normal for a while. I'd have voltage leaks, shorts to ground, blown fuses all over the place, codes would reappear instantly, and my engine would run like $hite.
So. I rip into the ECU, and low and behold, (see pic below) one of the two capacitors on the board has puked all over the PCB, crossing about 8 traces straight from the harness to the ECU. (see the pic below, sorry it's blurry). It's eaten through the surface layer and is crossing signals from all those sensors to the processor. The other one is starting to leak too.
My heart sinks when I see the greenish/blue long line after cleaning and letting it sit while I ordered replacement capacitors. That means it's eaten all the way through the surface coating to the copper, and oxidized it. Maybe the rest are burned a bit, but those two are likely beyond my ability to repair. (I could repair large traces with solder, but these are TINY)
I solder on new caps, clean the surface a bit more, spray liquid electrical tape on the surface to prevent further oxidization, button it up and pray.
Two days without any codes.... and then today... P0152 came on. Nothing else at this point, but I believe I caught the issue too late. Those traces are fried. I now have to replace the ECU.
