2011 Hyundai Sonata 2.4L GLS 6 Speed Manual - A lot of problems

Maintenance/Repairs
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1

I’ve always been one to do my own work instead of dealing with shops charging a fortune for easy repairs.
I have had a lot of problems out my 2011 Sonata and I can’t quite figure out what the cause is.

About 6 months ago, I had to replace my MAP sensor (Barometric Pressure Sensor) due to it going out, as well as my power steering coupler.
When I replaced the MAP Sensor all went well and it was running smoothly. I replaced the coupler and ran into an issue when taking off my steering wheel. My air bag clock spring came unwound. Shortly after, my fuel level sensor, as well as my brake light switch went out. So within the past two weeks… I have replaced the clock spring, the fuel level sensor and the brake light switch. Now that all of that and said and done…

My fuel level sensor still does not work after replacement
Traction control light is always on saying I have no traction
Reverse lights went out like 2 days ago, both at the same time, I haven’t checked yet, but I believe it’s a fuse.
Check engine light came on yesterday, I used my OBD Scanner and pulled these codes:

P2110 - “Engine Performance - What the code definition basically means is that the vehicle has been forced into a “limp in condition”. Engine RPM’s are reduced to the point of the engine running just above idle so that the vehicle can be “limped in” to a repair facility or off the road into a parking lot, etc. without doing any further damage to it. The problem is usually with the vehicle’s transmission or one of the sensors that control it. Some examples are the Throttle Actuator Control (TAC) motor stuck, faulty TAC control, TAC wiring or connection problems to name a few. The vehicle should be taken to a professional automotive repair facility for an in-depth diagnosis.”

P0605 - Internal Control Module Read Memory (ROM) Error (I don’t have much information for this one)

P0106 - “Engine Performance - The Manifold Absolute Pressure/Barometric Pressure Circuit measures the air pressure inside of the intake manifold. If there is too little or too much air pressure, this sensor sends a signal to the vehicle’s computer which in turn makes adjustments to the air/fuel mixture, along with other adjustments, to keep the engine running smoothly. This sensor directly affects vehicle emissions. If the signal that is sent to the computer is compromised in any way, it will turn on the Check Engine Light and this code will set. A lack of engine performance will be noticed. A visit to a qualified repair facility for further diagnosis is recommended to repair this problem.”

P0463 - “Emission Controls - The Fuel Level Sensor is part of the Fuel Level Sensor Unit that is located inside of the fuel tank. As the Fuel Level Sensor float moves up and down with the level of fuel in the fuel tank, an electrical signal is created and sent to the vehicle’s computer which then creates its own signal to the fuel gauge which in turn shows the proper amount of fuel in the fuel tank. If too high of a voltage signal is sent to the computer it relates to an incorrect fuel level reading. Once this incorrect reading is recognized by the vehicle’s computer, it will turn on the Check Engine Light and set this trouble code. Due to the number of items that play into setting this code, a more detailed diagnosis will need to be performed at a reputable repair facility.”

I tried to start my car yesterday and it refuses to crank, which I believe comes down to the MAP Sensor messing with the Fuel Pump.

So I have come to this conclusion:

MAP Sensor is out again. (I believe this caused P0106 and P2110)
Fuel sensor still not working. (P0463)
Reverse lights I believe is a fuse, I have yet to check.
Traction Control Light stays on… (I thought this was the brake light switch causing this, but after replacement, it still stays on.)

I think a lot of this is coming down to my PCM crapping out on me, but I’m not 100% sure. I am stubborn about taking my car to the dealership but I think it’s about to come to that.

Does anyone have any idea what is going on?

2

From my perspective, this issue needs to be addressed first:

P0605 - Internal Control Module Read Memory (ROM) Error (I don't have much information for this one)

The drive-ability issues could all be attributed to the PCM. Figure this out first. It could easily require a trip to the dealer as the first step would be to try re-flashing the unit. It might not work but if it does, that could save a lot of $$$ versus replacement.

3
TwinTurboTwinTurbo Junior Grease Monkey

12:18PM

From my perspective, this issue needs to be addressed first:
P0605 - Internal Control Module Read Memory (ROM) Error (I don’t have much information for this one)
The drive-ability issues could all be attributed to the PCM. Figure this out first. It could easily require a trip to the dealer as the first step would be to try re-flashing the unit. It might not work but if it does, that could save a lot of $$$ versus replacement

Thanks for the fast response TwinTurbo, I just called the dealership and am waiting on a call back about the pricing and about their opinion on whether or not flashing the PCM would be a possible fix. I failed to mention earlier that I do have a sound system installed in my vehicle, nothing too big. The amp puts out about 800w, so it’s nothing that the stock alternator couldn’t handle. But about a year ago, I installed a 12v power switch in the dash to turn the system on and off… After a few weeks of operation, the switch had somehow moved and connected to some metal and shorted out. I’m not sure if this could have caused the PCM to short and started this snowball of issues I have going on. I will post updates on the situation once I finish talking with the dealers and decide if a re-flash of the firmware is something I want to do.

4

You might mention the power switch and the short that you had when you take it in.

5

This sounds like the problem I was having with my 97 Explorer.

a quick look at my FACTORY engine controls wiring diagram told me there was an always hot PCM memory fuse that needed checking. The fuse was blown, replaced it & problem solved.

6

Repair the MAP sensor problem before attempting to replace the PCM;

Applicable Vehicles:
Elantra(UD/MD/GD/JK): 2011
Genesis Coupe (BK) 2.0L: 2010
Santa Fe (CM) 2.4L: 2010 - 2012
Santa Fe Sport (AN): 2013
Sonata (NF) 2.4L: 2006 - 2010
Sonata (YF): 2011
Tucson (LM): 2010

Warranty Information:

Normal warranty applies.

Service Procedure:

When P0605 and P2110 are the ONLY two present DTCs:

Inspect the following component(s) operation and related wiring circuit.

^ Engine Coolant Temperature Sensor

^ MAP Sensor and Turbocharger Boost Sensor (MAP Sensor #2 for Turbo charging system)

^ Exhaust system modifications

When P0605 and P2105 are the ONLY two present DTCs:

^ Replace PCM

When P0605 and any other DTC(s) are present:

Inspect the accompanying DIG(s) related component(s) operation and wiring circuit(s)

(refer to the shop Manual for more details).

7

The traction control warning light is probably a result of the other problems, and not a problem itself. Work the other issues first. The manufacturer turns that warning light on when other systems fail b/c for it to work, it requires the other systems to also work properly.

The ROM error message is worrying. Suggest to contact a dealership shop to see if they’ve run into this before. This could be caused by an electrical glitch, like two wires were accidentally shorted together briefly. That kind of glitch could damage the engine computer’s circuitry. ROM means Read Only Memory, a type of memory that is programmed only once, at the factory when the car is made, usually has parameters that tell the engine computer how to make the engine run properly. Like the amount of ignition advance as a function of rpm and engine load. As part of the self-test feature the computer checks that ROM to make sure it is all there and readable & hasn’t changed since when it was first programmed at the factory. The diagnostic code says the computer thinks the contents of that memory have changed. That’s not a good thing.

You’ve already replaced a MAP sensor, and now getting another code for a MAP sensor? The MAP sensor is used in conjunction with the ambient temp sensor, the engine coolant sensor, and the pre-cat O2 sensor to set the amount of fuel to inject for the proper air/fuel ratio. It’s possible a problem with one of those other parts could be misinterpreted to be a problem with the MAP sensor. On my Corolla anyway it’s a fairly simple thing to test the MAP sensor using a hand-held vacuum pump and a dvm. The MAP tells the computer what the absolute intake manifold vacuum level is. By “absolute”, that means the reading is referenced to a total 100% vacuum. That’s why the MAP can also be used to tell the altitude, and is used by the engine computer for that function as well. Most vacuum measurements used in car diagnostics are referenced to ambient atmospheric pressure, so the MAP is a little different how it works in that respect.

8

The MAP sensor is used in conjunction with the ambient temp sensor, the engine coolant sensor, and the pre-cat O2 sensor to set the amount of fuel to inject for the proper air/fuel ratio. It’s possible a problem with one of those other parts could be misinterpreted to be a problem with the MAP sensor.

Well, not really George,that theory might entice someone to replace the ambient temp sensor, ECT sensor and oxygen sensors.

This is a MAP performance fault. The PCM compares the MAP values with TPS values, there is a correlation between the two along with engine speed that can be used to spot TPS or MAP failures. This fault may be telling you the TPS value was out of range at a specific moment, lets review freeze frame data. An exhaust restriction will also produce out of normal MAP values. There are other failure to look for, this requires a hands on inspection by an experienced technician.

Dare I say this is why shops charge “a fortune for easy repairs”. There is a value in having a vehicle repaired in one 2 hour visit and not spending weeks on a simple repair and replacing multiple parts. If a technician had broke your clockspring and damaged the brake light switch while replacing your steering shaft he would have or should have been held responsible for the damage but this one is on you, it seems to be less expensive to have a professional perform the repairs.

9

OP post:

P2110, P0605, P0106, P0463
... ...
When P0605 and P2110 are the ONLY two present DTCs:
Nope
When P0605 and P2105 are the ONLY two present DTCs:
Nope
When P0605 and any other DTC(s) are present:
Yep

Even so, I have a real hard time understanding the manufacturer’s logic/diagnostics for the first instance:
How can a bad MAP sensor result in a ROM error fault in the PCM diagnostics?? Either the programming is OK or it’s not. No external sensors should affect that…

10

It will be interesting to see what the problem turns out to be.

11

Here’s the current update.

My car is at the dealership awaiting maintenance.

Hyundai ran their Diagnostic and a few things popped up:

Several pieces of the Fuel Pump Assembly gone bad – being replaced.

MAP Sensor – Waiting until after fuel pump replacement to address if it’s still a problem.

Some steering sensor has went bad as well – Assuming this is leading to the Traction Control light remaining on.

They did not read these codes at all: P2110, P0605

But for some odd reason they popped for me.

Will update as soon as fuel pump is replaced.