Code P 1682 ........
Thread Starter
Team Owner
Joined: Feb 2000
Posts: 45,002
Likes: 892
From: Texas
CI 1-4-5-8-9-10 Vet
St. Jude Donor '03 thru '10, '17
Code P 1682 ........
Code P 1682 sets if the ECM detects a difference in the voltage levels of the two main power inputs to the ECM. Basically, the code will be stored when one voltage input has a significantly different value than the other one. Often a wiring faults, including corrosion on terminals, is at least a part cause.
This does make sense. About a month ago, I started my 2008 up and it ran like crap, shuddering, felt like it was running on 3 cylinders, then the "reduced power" message came up. I shut it down. Was bumming about spending several thousand $......then I remembered what I'd read here about low voltage. So I removed the battery cables, thoroughly cleaned the cables and posts, restarted - voila!! Problem solved. Runs great. I've driven it about 5 times, for a total of 60 miles and it runs great. But I do still have an engine light. I borrowed a scan tool and it only has the one code. Questions:
1. will this code prevent it from passing TX state inspection?
2. assuming I fixed the problem, will it clear itself after xx number of ignition cycles?
This does make sense. About a month ago, I started my 2008 up and it ran like crap, shuddering, felt like it was running on 3 cylinders, then the "reduced power" message came up. I shut it down. Was bumming about spending several thousand $......then I remembered what I'd read here about low voltage. So I removed the battery cables, thoroughly cleaned the cables and posts, restarted - voila!! Problem solved. Runs great. I've driven it about 5 times, for a total of 60 miles and it runs great. But I do still have an engine light. I borrowed a scan tool and it only has the one code. Questions:
1. will this code prevent it from passing TX state inspection?
2. assuming I fixed the problem, will it clear itself after xx number of ignition cycles?
Race Director
Joined: Dec 2013
Posts: 12,501
Likes: 3,627
P1682 Ignition 1 Switch Circuit 2 ECM
Would put a tech II on the car to double check, but if the car passes is self tests 5 times during start ups, it should clear the code to shut the light off, and just store the code as happened in past event memory instead.
So dash light, your not going to pass smog, but as stated, if you solved the problem, then car should turn the light/problem off after 5 times the car is started/it runs is self tests instead. If you have started the car, run it, and the light is still on, you did not fix the entire problem.
Would put a tech II on the car to double check, but if the car passes is self tests 5 times during start ups, it should clear the code to shut the light off, and just store the code as happened in past event memory instead.
So dash light, your not going to pass smog, but as stated, if you solved the problem, then car should turn the light/problem off after 5 times the car is started/it runs is self tests instead. If you have started the car, run it, and the light is still on, you did not fix the entire problem.
Safety Car
Joined: Jul 2013
Posts: 4,408
Likes: 3,484
From: Granada Hills CA
Looks like you solved your problem. Hopefully the CEL will turn off after a few more trips. Your post is one of the few times I have seen "voila!" spelled correctly on this board so that gave you extra good karma!
Thread Starter
Team Owner
Joined: Feb 2000
Posts: 45,002
Likes: 892
From: Texas
CI 1-4-5-8-9-10 Vet
St. Jude Donor '03 thru '10, '17
P1682 Ignition 1 Switch Circuit 2 ECM
Would put a tech II on the car to double check, but if the car passes is self tests 5 times during start ups, it should clear the code to shut the light off, and just store the code as happened in past event memory instead.
So dash light, your not going to pass smog, but as stated, if you solved the problem, then car should turn the light/problem off after 5 times the car is started/it runs is self tests instead. If you have started the car, run it, and the light is still on, you did not fix the entire problem.
Would put a tech II on the car to double check, but if the car passes is self tests 5 times during start ups, it should clear the code to shut the light off, and just store the code as happened in past event memory instead.
So dash light, your not going to pass smog, but as stated, if you solved the problem, then car should turn the light/problem off after 5 times the car is started/it runs is self tests instead. If you have started the car, run it, and the light is still on, you did not fix the entire problem.
Thread Starter
Team Owner
Joined: Feb 2000
Posts: 45,002
Likes: 892
From: Texas
CI 1-4-5-8-9-10 Vet
St. Jude Donor '03 thru '10, '17
Race Director
Joined: Dec 2013
Posts: 12,501
Likes: 3,627
Check with the local guys that may have a tech II to put on the car.
The car goes through self tests every start up (two of them), and if a problem resolves it self in enough test, then the car will cancel the active DTC. Also, if the car does pass the self test and the code is still active, you can clear it with the Tech II as well.
As from there if still problem, you can either fix the problem, or just go in with a Hp tuner or EFI live to shut off the code from being re-acitaved if you need to get the car through smog, but don't have the time right away to fix the problem instead. Hence with the HP tuner method, you still have the problem, but is not going to throw a DTC to shut you down during a smog test.
The car goes through self tests every start up (two of them), and if a problem resolves it self in enough test, then the car will cancel the active DTC. Also, if the car does pass the self test and the code is still active, you can clear it with the Tech II as well.
As from there if still problem, you can either fix the problem, or just go in with a Hp tuner or EFI live to shut off the code from being re-acitaved if you need to get the car through smog, but don't have the time right away to fix the problem instead. Hence with the HP tuner method, you still have the problem, but is not going to throw a DTC to shut you down during a smog test.
Thread Starter
Team Owner
Joined: Feb 2000
Posts: 45,002
Likes: 892
From: Texas
CI 1-4-5-8-9-10 Vet
St. Jude Donor '03 thru '10, '17
Check with the local guys that may have a tech II to put on the car.
The car goes through self tests every start up (two of them), and if a problem resolves it self in enough test, then the car will cancel the active DTC. Also, if the car does pass the self test and the code is still active, you can clear it with the Tech II as well.
As from there if still problem, you can either fix the problem, or just go in with a Hp tuner or EFI live to shut off the code from being re-acitaved if you need to get the car through smog, but don't have the time right away to fix the problem instead. Hence with the HP tuner method, you still have the problem, but is not going to throw a DTC to shut you down during a smog test.
The car goes through self tests every start up (two of them), and if a problem resolves it self in enough test, then the car will cancel the active DTC. Also, if the car does pass the self test and the code is still active, you can clear it with the Tech II as well.
As from there if still problem, you can either fix the problem, or just go in with a Hp tuner or EFI live to shut off the code from being re-acitaved if you need to get the car through smog, but don't have the time right away to fix the problem instead. Hence with the HP tuner method, you still have the problem, but is not going to throw a DTC to shut you down during a smog test.
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