# Backup Light Switch Location and Jerk when letting off Brake.



## cooter2 (Oct 8, 2018)

Hello, new Cruze owner here!

I recently bought a higher mileage 2014 Cruze Diesel with a few issues. I have been working through the various issues and have two that I would like some help with. 

1. Does anyone know the location of the backup light switch? I assume its on the tranny somewhere. My backup lights are not working, no power at the socket when in reverse. However they work when the car has been parked for the courtesy lighting. I am going to assume backup light switch, just don't know where the sensor is. 

2. My car jerks if I am sitting at a stop (the car seems to go into neutral). When I then let off the brake (sometimes, not consistently), the car will jerk into gear, kinda like if I would drop the clutch on a manual. I found that if I let off the brake slowly or mess with the brake petal, it will not jerk. With that and some reading, my guess is the brake position sensor is bad. Bought a new one, but don't have a scanner that will allow me to re-calibrate it when I put the new one in. Anyone have any other ideas on this one that I can consider?

I'm coming from a 2004 VW Jetta TDI. So far I am liking the modern conveniences this car brings. It definitely does not get the fuel mileage that my Jetta did. I do mostly highway driving to work, i think I am around 40 or so, Jetta did about 45. 

Also wondering about tuning. Does anyone have any real world feedback on if there are significant mpg increases with tuning (and removing all that extra stuff on the front of the engine...).


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## Rivergoer (Mar 30, 2017)

Welcome aboard and congrats on the Gen 1 diesel...excellent choice!

Can’t help ya on the first couple of questions, perhaps others will chime in though.

As for the tuning and ‘weight reduction’ here are a couple helpful links to get u started:

DIY How To

Recent Feedback


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## mechguy78 (Jun 6, 2016)

I was doing a bulb check on my 14 1LT gas Cruze and found that the engine had to be running for the reverse lights to come on.


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## cooter2 (Oct 8, 2018)

mechguy78 said:


> I was doing a bulb check on my 14 1LT gas Cruze and found that the engine had to be running for the reverse lights to come on.


crap...that makes it more entertaining to test by yourself.


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## ChevyGuy (Dec 13, 2014)

cooter2 said:


> crap...that makes it more entertaining to test by yourself.


See if you can find a light colored wall you can back up to at night. You should be able to check it with your side rear view mirrors.


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## ChevyGuy (Dec 13, 2014)

cooter2 said:


> My car jerks if I am sitting at a stop (the car seems to go into neutral). When I then let off the brake (sometimes, not consistently), the car will jerk into gear, kinda like if I would drop the clutch on a manual. I found that if I let off the brake slowly or mess with the brake petal, it will not jerk. With that and some reading, my guess is the brake position sensor is bad. Bought a new one, but don't have a scanner that will allow me to re-calibrate it when I put the new one in. Anyone have any other ideas on this one that I can consider?


I think some have reported success in just changing it. 

It may also be that the car needs to learn how you use the brake so it knows when to engage the clutch. I know there's some kind of learning going on, and that makes the most sense to me.


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## cooter2 (Oct 8, 2018)

ChevyGuy said:


> I think some have reported success in just changing it.
> 
> It may also be that the car needs to learn how you use the brake so it knows when to engage the clutch. I know there's some kind of learning going on, and that makes the most sense to me.


So the calibration is no big deal? And are you also saying others have had this issue and fixed it by swapping out that sensor?


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## Rivergoer (Mar 30, 2017)

@MP81 had similar issues with his diesel Aisin tranny recently. He and others reported placing it in Manual mode made the symptoms disappear. Some had transmission replacements under PT warranty.

Here’s a LINK to the recent thread...hope this helps.


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## ChevyGuy (Dec 13, 2014)

cooter2 said:


> So the calibration is no big deal? And are you also saying others have had this issue and fixed it by swapping out that sensor?


I think they had problems with a failing sensor and just swapped it. That, along with the problems of a brake pedal that didn't fully return suggested that the car will "learn" the sensor over time. The tool just means it's fully educated by the time it gets back to the driver.


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## Blasirl (Mar 31, 2015)

Welcome Aboard!:welcome:

I put a cheap door mirror sideways on the garage door inside - no room on the wall. Makes it soooo much easier to see lamps.

Don't forget to introduce yourself and your Cruze here.


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## cooter2 (Oct 8, 2018)

ChevyGuy said:


> I think they had problems with a failing sensor and just swapped it. That, along with the problems of a brake pedal that didn't fully return suggested that the car will "learn" the sensor over time. The tool just means it's fully educated by the time it gets back to the driver.


Okay, I'll just try to swap the sensor, its sitting in my passenger seat now anyway. 

And just I did the intro, thx.


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## cooter2 (Oct 8, 2018)

Okay, looks like I got the backup light situation figure out. Was more my imagination then anything....The previous owner had LED's in it. one of them was inserted in a way where it was not working. That is all good now.

Going to try to put the brake sensor on in the next few days. 

I spent today replacing the rear brakes (a pad unbonded from the steel part that holds it) and fixing my backup assist/side sensors (side sensors were extremely corroded, like more then any of the pics I saw on here, and the harness was blowing fuses without anything plugged into it....got that all fixed, only issue is it still says "service side detection system" even though the mirrors now light up and the car beeps and the fuse don't blow).


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## cooter2 (Oct 8, 2018)

cooter2 said:


> Okay, looks like I got the backup light situation figure out. Was more my imagination then anything....The previous owner had LED's in it. one of them was inserted in a way where it was not working. That is all good now.
> 
> Going to try to put the brake sensor on in the next few days.
> 
> I spent today replacing the rear brakes (a pad unbonded from the steel part that holds it) and fixing my backup assist/side sensors (side sensors were extremely corroded, like more then any of the pics I saw on here, and the harness was blowing fuses without anything plugged into it....got that all fixed, only issue is it still says "service side detection system" even though the mirrors now light up and the car beeps and the fuse don't blow).


Replaced the brake position sensor and for a couple days now the issue has gone away. Hopefully that was the issue with it jerking when stopped!


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## KpaxFAQ (Sep 1, 2013)

If you do the DPF, SCR, and EGR delete from Oz Tuners you'll get over 50MPG...depending on how fast you drive. I find anything over 70MPH and it starts to drop more than the extra speed is worth. 80MPH I get the factory rating of 45-46MPG. 70MPH I get around 50MPG, and 55-60MPH I can get 52-55MPG.


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## sailurman (Sep 29, 2016)

I get the same MPG stock.


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## cooter2 (Oct 8, 2018)

KpaxFAQ said:


> If you do the DPF, SCR, and EGR delete from Oz Tuners you'll get over 50MPG...depending on how fast you drive. I find anything over 70MPH and it starts to drop more than the extra speed is worth. 80MPH I get the factory rating of 45-46MPG. 70MPH I get around 50MPG, and 55-60MPH I can get 52-55MPG.


How much of an increase over stock was it for you? 



sailurman said:


> I get the same MPG stock.


How fast do you drive? NE Speed limits were recently increased and I live in a rural area where 65-70 mph is posted, I usually do 70-75 (hilly as well). What do you get for mpg at that speed?


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## sailurman (Sep 29, 2016)

cooter2 said:


> How fast do you drive? NE Speed limits were recently increased and I live in a rural area where 65-70 mph is posted, I usually do 70-75 (hilly as well). What do you get for mpg at that speed?


70-75 I'm doing about 50 plus or minus 2MPG. I drive in Phoenix, AZ so the roads are very flat and well maintained. I ride share during spare time which puts my overall average MPH at about 30, but I still pull 37 MPG overall.


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## KpaxFAQ (Sep 1, 2013)

cooter2 said:


> How much of an increase over stock was it for you?
> 
> 
> 
> How fast do you drive? NE Speed limits were recently increased and I live in a rural area where 65-70 mph is posted, I usually do 70-75 (hilly as well). What do you get for mpg at that speed?


70-75MPH on rolling hilly terrain gets me 47-48ishMPG. I never really was able to blow the doors off the stock 46MPG without some creative driving or optimal conditions myself. 

The delete gave me a solid 3-5MPG increase. This includes around town short trip driving as well where my mileage becomes particularly dreadful. 

I see you're in Nebraska...About a week ago I cut a piece of aluminum flashing to perfectly fit the grill opening on the front using a few zip ties. The vehicle warms up noticeably faster now which will get better mileage and faster heat. My rule of thumb is consistent 60 degree and below I put the block on for the winter. The bottom shutters can easily open if needed.


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## Cruzediesel81 (Oct 28, 2018)

I had a jerk when I let off brake at stop at around 60000 miles and had to get a transmission change under warranty. It got worse too before I got a new one


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## cooter2 (Oct 8, 2018)

Cruzediesel81 said:


> I had a jerk when I let off brake at stop at around 60000 miles and had to get a transmission change under warranty. It got worse too before I got a new one


I have done quite a bit of reading on this. Looks like it is a somewhat known issue. The first step I am going to take is to change the tranny fluid, not sure if it was ever changed before and is a quick, cheap easy try. 

If that don't work, the next step I am going to take is to replace the solenoids in the Valve Body. From what I have read online and seen in some random videos I found, the solenoids in the valve body can wear and catch especially when they get warm (which is what I have found). There is alot I found online about rebuilding the solenoids, but it looks like I can get a whole set for a few hundred $$$ and the valve body is apparently on the front of the tranny in a place I may be able to get to relatively easily. I suppose I could test each solenoid individually, but if I am going to have it apart, I am just going to do them all so I am not wasting my time.....

Something like this: https://www.amazon.com/AW6AX-EL-Tra...ie=UTF8&qid=1541007579&sr=8-9&keywords=AF40-6

If I knew which solenoid specifically was used for the neutral -> first shift, then I would just swap that one. Have yet to have figured that part out.....

Here is some info on it: https://www.sonnax.com/tech_resources/192-aw-6-speed-fwd


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