Haunted Computer
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Racer
Joined: Oct 2010
Posts: 277
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Haunted Computer
My 2010 Vert is basically a daily driver if it's not snowing. The other day I started it and got a msg that the active handling needed service, and oh by the way reduced power. Check engine light was on. Let it sit for a while. Check engine light still on active handling reduced power gone. (Random low coolant in days past). Fired her up this morning. No warning lights for a couple of miles then the active handling reduced pwr came on. Then after driving 30 highway miles and letting it sit for a couple of hours. Reduced power gone, but now hi temp, A/C off! WTF! Its been sitting ! wasn't over heating. Gauge was 100 F and no sign of hi temp. I'm planning to see if NAPA's code reader has a clue. Then disconnect the battery and reset the computer. Any advise would be appreciated
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Joined: Sep 2013
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From: Cape Coral, Florida
My 2010 Vert is basically a daily driver if it's not snowing. The other day I started it and got a msg that the active handling needed service, and oh by the way reduced power. Check engine light was on. Let it sit for a while. Check engine light still on active handling reduced power gone. (Random low coolant in days past). Fired her up this morning. No warning lights for a couple of miles then the active handling reduced pwr came on. Then after driving 30 highway miles and letting it sit for a couple of hours. Reduced power gone, but now hi temp, A/C off! WTF! Its been sitting ! wasn't over heating. Gauge was 100 F and no sign of hi temp. I'm planning to see if NAPA's code reader has a clue. Then disconnect the battery and reset the computer. Any advise would be appreciated
Melting Slicks
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From: Pittsburgh PA
St. Jude Donor '10-'11-'12-'13-'14
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From: Paris
I disagree to some extent. From my experience, computer issues can be related to a bad battery but I would strongly suggest checking that all ground connectors are working well and not rusted. I usually spray mine now and then to clear up the oxidisation but there are 2 connectors just under the battery that require removal of the battery holder.
My wonky computer issues were related to corroded ground connectors (the two under the battery) and one cable in the harness to the ECM that was corroded (probably due to the person creating the harness slicing the insulation at the factory, thereby exposing the copper to the elements and rust away).
Suggest you pull codes, look which harness is in the way and check contacts/conductivity.
My wonky computer issues were related to corroded ground connectors (the two under the battery) and one cable in the harness to the ECM that was corroded (probably due to the person creating the harness slicing the insulation at the factory, thereby exposing the copper to the elements and rust away).
Suggest you pull codes, look which harness is in the way and check contacts/conductivity.
Thread Starter
Racer
Joined: Oct 2010
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Cro orange. What you say makes sense. I'll take a look at the connectors and see if I can find the one you mentioned on the ECM. The only other thing that could be a possibility is that the starter is such an electrical drain that hitting the starter might lower the voltage enough to cause a computer problem.
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From: Paris
I would still suggest pulling codes first to see where to start, those codes are very handy actually
You may notice that when the car starts a few things are powered off, I assume as a form of protection from the power surge.
You may notice that when the car starts a few things are powered off, I assume as a form of protection from the power surge.
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Joined: Sep 2013
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From: Cape Coral, Florida
Cro orange. What you say makes sense. I'll take a look at the connectors and see if I can find the one you mentioned on the ECM. The only other thing that could be a possibility is that the starter is such an electrical drain that hitting the starter might lower the voltage enough to cause a computer problem.
Race Director
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Gotta LOVE Hi Tech stuff.......When it works!! I'll go with the battery, too. How old is it? I never realized how voltage sensitive these cars are.
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Racer
Joined: Oct 2010
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LOL pulled the battery but didn't see any ground connections? Cleaned and lubed the terminals, tried to raise the top...... yeah, indexed the windows, raised the top. Everything was great for about 5 miles. Service TPMS left rear wheel. That actually the right rear wheel but that's a different story. I'm thinking that's a separate problem. As I said, that's a different story. The battery is a couple of years old. I don't think that's a problem. But, I'm going to put it on a battery tender every night to see if the problem goes away. Batteries aren't cheap, but less expensive than a trip to the LD
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From: Paris
You have to remove the battery holder that held in place by 4 bolts in order to see the ground connections underneath, if that was your point.
Honestly, you need to pull the codes to see what is going on, anything else is equivalent to shooting in the dark.
Honestly, you need to pull the codes to see what is going on, anything else is equivalent to shooting in the dark.
Racer
Joined: Oct 2019
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From: Mn
You need to read the code otherwise you are just looking for a needle in a hay stack. Mine was a P0601 code with the same message on the dashboard. This might be an ECM. Rock Auto will get one for you but it might be a couple of months. Get on the waiting list! I hope this helps. Let us know.
Thread Starter
Racer
Joined: Oct 2010
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Disconnecting the battery worked for a while but it happened again. This time It only worked for about 10 miles. So, I followed your advise and had the code pulled. It's been a long time since I swapped a thermostat but I can't see that being a problem. the coolant is cold! I don't see what difference it makes to the computer weather the thermostat is open or closed. It's definitely not hot! So. I'm thinking it's the temp sensor. What do you guys think?
Moderator, Tech Contributor
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From: Cape Coral, Florida
The ECM not only want to make sure the ECT is to high but also too low…a warmer engine reduces emissions so that’s why it’s throwing the P0128…if you think it’s the ECT sensor let the car sit overnight and with your code reader see what your coolant temp reads…it should be within a few degrees of the outside air temp…if your code reader has a global OBD2 function ( check engine light symbol) check the ECT there…what you see as far as ECT is the temperature the ECM is seeing…there is something called “substituted values” in scan data which I won’t get into here.