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Help!!! "Run mode change system check" coolant temp gauge pegged hot, etc


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So I changed the injectors on my 2008 LGT and put in TGV deletes while I was at it.

 

Deletes went in fine. Injectors too. After everything was seated we plugged in all the clips we had unplugged to get the intake manifold up and out of the way to work. Everything seemed fine, fuel pump primed, injectors didn't leak...cool.

 

We went ahead and bolted everything else back up and thought we were finished. But when I turned the key the fuel pump didn't prime. The temp gauge is pegged all the way hot. The fans came on. And my AP won't connect to the ecu. Also if you try to crank it over nothing happens. The "Run mode check system change" error came across the dash.

 

I already went and tested my battery to see if that was the issue cause after research that was a possibility....my battery is fine.

 

Checked all grounds (only one I touched was the driver side TGV, I think) is there another ground I am missing maybe? All the clips are connected that we unplugged.

 

I can't figure out what the hell it is.

 

Any ideas? Thanks in advance.

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Check the brown plug on the passenger strut tower?

You mean the giant wiring harness? That is definitely plugged in. I'll check for this brown one you speak of. What is it to?

Go get a bit to eat, take a deep breath, go back over everything you did, you'll find something you missed.

Thanks man, I've taken a lot of breaks and every took everything apart again to look for anything I missed, no luck so far :confused:

Grounding block behind drivers TGV

You mean the one that the main battery ground goes to and thats by the starter? I never touched that one and I double checked it too.

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Nothing worked...took it to a friends shop that all he does is build Subarus, Evos, Nissans, etc.

 

Ended up finding that it looks like one of the injector clips wiring got crushed and pinched, if that shorted out it probable fried something. We then talked to his friend that is a master tech at Subaru and he told him to try us to try a ton of stuff to no avail. It's now at the stealership getting a $120 diagnostic test to see if they can figure it out with their super fancy master computer.

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Nothing worked...took it to a friends shop that all he does is build Subarus, Evos, Nissans, etc.

 

Ended up finding that it looks like one of the injector clips wiring got crushed and pinched, if that shorted out it probable fried something. We then talked to his friend that is a master tech at Subaru and he told him to try us to try a ton of stuff to no avail. It's now at the stealership getting a $120 diagnostic test to see if they can figure it out with their super fancy master computer.

 

That being the SSM, which isn't very fancy, if you've ever seen it. It's like a souped-up Gameboy.

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Sounds like when I fried my ECU. Was the dealer able to connect to the ECU with the SSM?

Go to http://www.car-part.com and get another ECU for ~$150.

Find your key security code and have your friend barrow the SSM to reprogram the new ECU to your BIU. Give your friend a case of beer.

 

Is your AP married to the ECU?

Call Cobb and tell them your ECU is fried and the AP was married to it. Send them the AP and ECU, and they'll send your AP back un-married. They'll want the ECU to verify it is fried. If I remember correctly, it was like $45 to get the AP un-married.

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  • 2 months later...
There is a ground with an eye loop and a bolt that threads into the rear of the drivers side injector guard. Its hard to see because I believe there is a hose or a wiring harness that is right above it that will block you view when looking from above. I ran into the exact same issue several months ago and this is what I found. I had started the bolt into the nutsert of the guard but never tightened it.
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  • 3 years later...

Hi. This old thread is the last hope for my Run Mode Change System Check issue. I have done everything suggested in every thread I can find online.

 

Is the main fuse you speak of inline somewhere! Or is it in one of the two fuse box locations? I have the ECU exposed and don’t see one there.

 

Please give me some detail on location, or size, or ?

 

Thanks much.

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Hi. This old thread is the last hope for my Run Mode Change System Check issue. I have done everything suggested in every thread I can find online.

 

Is the main fuse you speak of inline somewhere! Or is it in one of the two fuse box locations? I have the ECU exposed and don’t see one there.

 

Please give me some detail on location, or size, or ?

 

Thanks much.

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Hi. This old thread is the last hope for my Run Mode Change System Check issue. I have done everything suggested in every thread I can find online.

 

Is the main fuse you speak of inline somewhere! Or is it in one of the two fuse box locations? I have the ECU exposed and don’t see one there.

 

Please give me some detail on location, or size, or ?

 

Thanks much.

 

I think it was one of the gray fuses under the hood. I am not sure though. You can use a DMM to go through and check them all. What lead to this issue?

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Edit: sorry for how long this reply is, and I don't mean to threadjack.. just hoping someone might be able to help him out.

 

I see roscoe made a few posts in the warranty section, unfortunately I think that section may get overlooked from time to time. Here are the threads with the issues he had/has.

 

https://legacygt.com/forums/showthread.php/run-mode-change-system-check-275651.html?p=5830793#post5830793

I have spent a week stuck on the side of the road, sleeping in my 2008 OBXT (5EAT), and pouring over this forum, others, and searching other sources for answers. I have the same symptoms as others when I try to start the car: ACC behaves normal, turn key onward to ON and gauges sweep and lamps test normally, but then radiator fans kick on, coolant temp gauge pegs, radio console and climate go dark. When I turn key to engage the starter, nothing. No click, no moan, no dimming. Then I see the message RUN MODE CHANGE SYSTEM CHECK on the dash.

 

When did it start? Well, after I pulled the intake manifold and the main engine harness to do some maintenanc and repair. I had a coolant leak, vAcuim leak, and a couple connectorsnin the harness that needed attention. The car has not started since.

 

I have taken each step offered here: Cleaned all grounds on the frame, engine block, heads, and paid very special attenttion to the harness ground luggs on the harness, which bolt to a dedicated spot on the Bank 2 fuel rail protector. Each of the grounds now show no more than .2mA of resistance.

 

I have removed the harness and reattached every connector, paying my close attention to each connector to make sure there are no broken wires or shorts.

 

Ensured. the CTS connector is not attached to the EVAP sensor, and vice versa. The connectors are almost identical and close enough that it is possible to mix them up. And, as I read here, the symptoms of mixing them up would mimic what I am seeing wrt gauge and fansb. Actually I tried both ways, same issue, and returned them to color coordinated state: grey connector to the grey CTS and black connector to the Black EVAP sensor;

 

Installed a new Red Optima AGM battery with 1000 CA, 800CCA, 50 Amp hour and 100 RC whatever that is. When I installed the battery it showed 12.7vdc across the terminals. One day later is it 12.2vdc. Parasitic Drain maybe? I have used the inside lights a bit, maybe a half

Hour tops. And have tried to start the car maybe 29 times in that span.

 

Reseated the main and secondary harness connectors. Reseated the transmission harnesses. And checked under the dash on both sides for loose connections.

 

I have cleaned the starter contacts, and made sure the transmission grounds are as sound as those up front.

 

I have continuity tested, reseated, and tested again every fuse in the car except for the airbag fuses. And I have pulled the starter relay and swapped it with the seat heater relay, which appears identical in shape, function and capacity.

 

As I am not gonna be going anywhere until

This is resolved, I should be able to take advise or answer questions readily. Any thoughts? Advice? Amusing anecdotes?

 

I have food and water. And unless it gets real cold, I’m I. Good

Shape. And I’m retired and single and nobody is expecting me home. Sort of liberating.

 

One other thing that seems odd: measuring voltage across the battery terminals shows 12.2vdc today, but if Indiaconnect the negative cable and measure voltage between the cable connector and the negative Battery terminal, I see 11.7vdc. Shouldn’t that reading be the same as across the terminals? Why the voltage drop? Help please.

 

 

https://legacygt.com/forums/showthread.php/battery-voltage-question-x2-275652.html?p=5830807#post5830807

I am posting this seperately from my larger post in this forum concerning my no crank issue (Run Mode Change System Check). This is purely

Battery related:

 

Brand new Red Optima battery showed 12.7vbc yesterday when I installed it. Today it shows 12.2vdc after running my backseat reading light for about half an hour and trying to start my no crank car 20 times.

 

1. Does this suggest a parasitic drain?

 

As of ten minutes ago, I see that 12.2 vdc across the positive and negative battery terminals, with cables attached. But if I disconnect the negative cable and measure voltage between it and the negative battery terminal, I see

11.7 vdc.

 

2. Shouldn’t I see the same 12.2 vdc on the negative side?

 

Thanks for your insights.

 

https://legacygt.com/forums/showpost.php?p=5830700&postcount=930

2008 OBXT - Original owner. 140,000 easy trouble free miles until the stealerhip in Conshohocken PA got their hands on it to replace a blown out turbo and put in a new timing belt. Big mistake. I normally turn the wrenches on my cars and bikes, but I was living in an apartment building that wouldn’t allow me to do any of it In the Parking lot. Two weeks after I got the car back the bolt holding tensioner in place broke and the Belt slipped, then shredded, and let’s just say there was ‘interference’ in the valve train. Dealer said it was a bad bolt. Subaru Americ said poor workmanship by dealer. I say the tech used air to tighten it and was way over torqued. We all argued for a week or two, with me insisting on a new crate motor, SA insisting the dealer

Pay for it, and the dealer holding out for SA to pay half. Instead, the same

Tech fixed it, top end only, and they billed me $0 but I have had problem with the car ever since. I had to replace HGs 15,000 miles later and as I disassembled it became clear to me that the Dealership in Conshohocken has no oversight on the Techs and apparently no quality control. Bolts missing...torque specs ignored, One valve cover had OEM gasket with silicone in right spot, other

Had only silicon. And there was no thermostat installed.....in PA.

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I think it was one of the gray fuses under the hood. I am not sure though. You can use a DMM to go through and check them all. What lead to this issue?

 

Thanks for getting back, and yeah, I didn’t help myself much when I posted it there. Thought it was for Warrenty AND maintenance problems. Thanks for reposting.

 

So it was in the engine bay fuse box. By grey, was it a relay?

 

Clearly I did something wrong when I pulled the intake (including TGVs) to tap a

New thread into block for the coolant passage. It ran before that, and has not turned over since. To try and paraphrase my efforts to resolve, I have:

 

1. replaced battery (new Red Optima), alternator (reman NAPA) , and the main engine harness (eBay).

 

2. I have cleaned and verified the grounds on the frame rails (both sides) and the motor/transaxle, the injector rail protector on drivers side, the five ground points below the Intercooler, starter ( including the positive terminal andnthe positive trigger spade connector), grounds on the strut towers, and the main battery ground.

 

3. I have checked every fuse I can find on the car. Both fuse

Boxes. There may be more. I have not identified any fusible links though. If there are any on the 08 OBXT, I would appreciate learning where. I used a simple continuity test on my DMM. L

 

 

Another thing: The dealer in Ventura California performed the airbag recall about two weeks before I pulled the intake. Is it conceivable that they did something undersash that was a ticking bomb? I have looked under dash on both sides for loose connectors and grounds. Didn’t find any ground straps at all.

 

I still feel as if the manifold ground is suspect. The two lug-pairs (4 wires each) are well grounded to the fuel rail protector and show .1 ohm resistance across that union, and the same from luges to battery negative terminal. Is there more I should

Check on the mnifold? can I verify this with a DMM? It’s plastic. Do any of the sensors attached to it require a local “frame” ground? Or are these grounded by the harness to the fuel rail protector?

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I think it was one of the gray fuses under the hood. I am not sure though. You can use a DMM to go through and check them all. What lead to this issue?

 

Thanks for getting back, and yeah, I didn’t help myself much when I posted it there. Thought it was for Warrenty AND maintenance problems. Thanks for reposting.

 

So it was in the engine bay fuse box. By grey, was it a relay?

 

Clearly I did something wrong when I pulled the intake (including TGVs) to tap a

New thread into block for the coolant passage. It ran before that, and has not turned over since. To try and paraphrase my efforts to resolve, I have:

 

1. replaced battery (new Red Optima), alternator (reman NAPA) , and the main engine harness (eBay).

 

2. I have cleaned and verified the grounds on the frame rails (both sides) and the motor/transaxle, the injector rail protector on drivers side, the five ground points below the Intercooler, starter ( including the positive terminal andnthe positive trigger spade connector), grounds on the strut towers, and the main battery ground.

 

3. I have checked every fuse I can find on the car. Both fuse

Boxes. There may be more. I have not identified any fusible links though. If there are any on the 08 OBXT, I would appreciate learning where. I used a simple continuity test on my DMM. L

 

 

Another thing: The dealer in Ventura California performed the airbag recall about two weeks before I pulled the intake. Is it conceivable that they did something undersash that was a ticking bomb? I have looked under dash on both sides for loose connectors and grounds. Didn’t find any ground straps at all.

 

I still feel as if the manifold ground is suspect. The two lug-pairs (4 wires each) are well grounded to the fuel rail protector and show .1 ohm resistance across that union, and the same from luges to battery negative terminal. Is there more I should

Check on the mnifold? can I verify this with a DMM? It’s plastic. Do any of the sensors attached to it require a local “frame” ground? Or are these grounded by the harness to the fuel rail protector?

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