Pivot
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- Joined
- Jul 2, 2017
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- 197
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MODS, PLEASE FEEL FREE TO MOVE IF THERE'S A MORE APPROPRIATE SECTION FOR THIS
Hi, all –
HERE’S THE SITUATION:
So, the truck behaves totally fine… until it doesn’t. My question is related to the fact that these things really only happen TOGETHER. It will randomly (and increasingly, over the last several weeks) pop the traction control light. Then it might not do it for two weeks. The errors showing in the DIC are “Service Stabilitrak” and sometimes “Automatic Collision Prep Unavailable”. The latter never shows without the former. Roughly 50% of the time, it is accompanied by the check engine light. Also, roughly 50% of the time (not aligned with the CEL), “park assist not available” and the reverse cam won’t engage. When that happens, it goes into limp mode and acceleration is trash.
Turn the truck off and all is well when I start it again, most times. Other times these things persist from the last ignition cycle. Rain doesn’t seem to be a factor. No hard or extreme driving conditions.
PULLED THE CODES:
P182B “Internal Mode Switch B Circuit Low Voltage”
P0700 “Transmission Control Module Requested MIL Illumination”
Of note, trans (knock on wood) is behaving normally. I’ve recently, maybe 15k ago, done the updated fluid full change and it’s been great since. Strong, even. No hard shifting.
POSSIBLE THEORIES:
* It feels electrical, since electricity is the only thing that these things seem to have in common, and they are sporadic. Battery is two years old, and standing, load, and charging all tested “OK”, although the battery did read that it could use a recharge, as it’s reading 80%. I WFH, so it sits in my driveway and doesn’t log a lot of miles in recent years. Prob going to trickle charge it for a full day this weekend.
* So I’m starting with changing the belts, likely this weekend, although they aren’t showing signs of exhaustion, since it’s time for that anyway. Hoping the main serpentine (for alternator) belt results in more consistent voltage, even though that hasn't been a specific issue. These modern vehicles can be really finicky with voltage inconsistencies.
* I’ve also read that P0700 can often be fixed by changing the alternator even though it's testing ok, since it may have diodes that can go bad, causing TCM malfunctions. No weird trans behavior.
* Cleaning speed sensors at the wheels. While I’m sure this can’t hurt, I’m not 100% convinced since the problem is sporadic, plus wth do they have to do with Collision Prep?
* I do have an OBD2 plugin – Xineering Magride delete. I’ve unplugged this to test and it doesn’t change the behavior.
So again I am trickle charging and changing the belts, and perhaps that will correct minor voltage variances that may be the cause. I don’t want to just start replacing everything since I’d have to wait up to two or three weeks to confirm whether the issue persists, and thought I’d see if anyone here has experienced this same combination of weirdness and/or has any wisdom to share.
Thanks
Hi, all –
HERE’S THE SITUATION:
So, the truck behaves totally fine… until it doesn’t. My question is related to the fact that these things really only happen TOGETHER. It will randomly (and increasingly, over the last several weeks) pop the traction control light. Then it might not do it for two weeks. The errors showing in the DIC are “Service Stabilitrak” and sometimes “Automatic Collision Prep Unavailable”. The latter never shows without the former. Roughly 50% of the time, it is accompanied by the check engine light. Also, roughly 50% of the time (not aligned with the CEL), “park assist not available” and the reverse cam won’t engage. When that happens, it goes into limp mode and acceleration is trash.
Turn the truck off and all is well when I start it again, most times. Other times these things persist from the last ignition cycle. Rain doesn’t seem to be a factor. No hard or extreme driving conditions.
PULLED THE CODES:
P182B “Internal Mode Switch B Circuit Low Voltage”
P0700 “Transmission Control Module Requested MIL Illumination”
Of note, trans (knock on wood) is behaving normally. I’ve recently, maybe 15k ago, done the updated fluid full change and it’s been great since. Strong, even. No hard shifting.
POSSIBLE THEORIES:
* It feels electrical, since electricity is the only thing that these things seem to have in common, and they are sporadic. Battery is two years old, and standing, load, and charging all tested “OK”, although the battery did read that it could use a recharge, as it’s reading 80%. I WFH, so it sits in my driveway and doesn’t log a lot of miles in recent years. Prob going to trickle charge it for a full day this weekend.
* So I’m starting with changing the belts, likely this weekend, although they aren’t showing signs of exhaustion, since it’s time for that anyway. Hoping the main serpentine (for alternator) belt results in more consistent voltage, even though that hasn't been a specific issue. These modern vehicles can be really finicky with voltage inconsistencies.
* I’ve also read that P0700 can often be fixed by changing the alternator even though it's testing ok, since it may have diodes that can go bad, causing TCM malfunctions. No weird trans behavior.
* Cleaning speed sensors at the wheels. While I’m sure this can’t hurt, I’m not 100% convinced since the problem is sporadic, plus wth do they have to do with Collision Prep?
* I do have an OBD2 plugin – Xineering Magride delete. I’ve unplugged this to test and it doesn’t change the behavior.
So again I am trickle charging and changing the belts, and perhaps that will correct minor voltage variances that may be the cause. I don’t want to just start replacing everything since I’d have to wait up to two or three weeks to confirm whether the issue persists, and thought I’d see if anyone here has experienced this same combination of weirdness and/or has any wisdom to share.
Thanks
