Stereo & Alarm problems

[NathanT 1]

Hi all,

 

Thread title gives you an idea of what's going on, but not specifics, so,

Alarm issue:

Every few days, when I lock my car with the buttons on my key, the alarm will start to beep, and after a minute, go off. This doesn't happen when I put my key in the door and lock it that way, and will sometimes stop for days, allowing me to lock it normally. I don't believe it's a sensor issue, as I've tested them all by holding down each sensor, & adding some bits of cardboard as padding to make sure the sensors are fully compressed while locking the car. It seems random when it happens, as it's happened in all kinds of weather, so any help on that would be appreciated.

UN-SOLVED: So it's been a few weeks since this happened, & my battery was either too low to support the stereo, or fully charged as I'd jump the car, then go for a long drive. I've since replaced the battery, & it still hasn't happened, so I'm assuming this was just a problem with the battery charge. If it happens again I'll re-edit this.

Re-edit: As stated above changed out the battery in the car & it hadn't happened since, until yesterday. Last thing I can try at home is changing the battery in the key, & if that doesn't work, guess it's back to Toyota to troubleshoot it.

 

Stereo problem:
I recently got a reverse cam, & was wiring it into the 12v cable on the back of the head unit. This 12v cable has had another cable wired into it for quite some time with no 'side effects', however, now there is nothing else wired into it. It's just the standard wire as if the loom was stock. Now when the key is inserted into the ignition & turned 1 notch, the stereo is powered on, however anything that affects the electronics, like the door being opened or closed reboots the stereo. When the key is turned again, as if to start the car, the stereo tries to power up, & fails, eventually turning off.

SOLVED: My battery was just too low for the car to sustain the stereo & all electronics. A jump to start the car solved this (probably should have tried that a lot earlier)

 

Any help with these problems would be a great benefit to me, & if any fixes are found in the meantime, I'll post them as replies, or edits.

[Jay 37]

Looks like improper grounding somewhere in the electrical system. It's like the current doesn't flow to the minus of the battery through it's usual path, but (partly) through your stereo  and/or alarm unit instead. Maybe you can measure the voltage between the minus of the stereo and the minus off the battery, while opening doors and turning the ignition key.

Good luck!

[NathanT 1]

Just tried to start the car with no luck, So jumped it, & the stereo seems to work, so maybe that was just a battery issue, which is surprising since i went for a 2 hour drive on saturday, so it should be fully charged. tbf my electronics knowledge with cars is pretty lack luster as never done anything like this before. I'm thinking my alarm beeping could be the same issue & my battery might just be on it's way out, but the car is only 4 & a bit years old at this point, so opinions on that are welcome as well.

[Jay 37]

Could be the battery, especially if a 48Ah one is fitted. As far as I know Toyota switched to 65Ah batteries.

[Church 209]

Not that sure. AFAIK new ones still came with 45Ah stock, but for many toyota replaced free of charge to 65Ah ones, if/when issues with flat battery appeared during warranty.

[NathanT 1]

8 minutes ago, Jay said:

Could be the battery, especially if a 48Ah one is fitted. As far as I know Toyota switched to 65Ah batteries.

 

1 minute ago, Church said:

Not that sure. AFAIK new ones still came with 45Ah stock, but for many toyota replaced free of charge to 65Ah ones, if/when issues with flat battery appeared during warranty.

Thanks for the info. I'll contact the garage & see if they'll replace the battery since it's within warranty.

[NJay 10]

12 hours ago, NathanT said:

 

Thanks for the info. I'll contact the garage & see if they'll replace the battery since it's within warranty.

Good luck

I tried and was rejected.

Told Toyota policy is that the batteries are not replaced under warranty if more than 11.5v and accepting charge. These cars don't start at much less than 12v which is already considered knackered by everyone else!

 

 

[Sleazyboii 2]

Hey bud, have you checked the bonnet sensor, i know you've said you've checked them all. I had a similar issue when i was messing with my car, I had bent the bonnet sensor giving the car the impression it was still open, had exact same issue could lock with key but when it comes to the fob it was having none of it. 

 

It was every so slightly bent on straightened the bracket up and its fine. 

[Beney86 10]

I actually had a weird issue with the Auto-Vox dash cam mirror, my car would stay in aux mode when i turned the car off- i couldn't lock the car using the key or fob. It would just beep at me, sometimes being a 5 second long solid beep. after about 1-2 mins of being away from the car i could then lock it. After about 3 months of this issue thinking it was wifi signals or a sensor problem with my car.I changed my key fob battery twice just incase. I finally noticed (i dont know how i didn't before) that the cash cam was not powering down when the car turned off and was drawing signal from the glove box connection. Being able to finally lock the car was due to the dash cam finally powering down. Unplugged the dash cam and never had the issue again. 

Probably completely unrelated to your issue, but maybe someone in the future might come across this

[NathanT 1]

2 hours ago, Sleazyboii said:

Hey bud, have you checked the bonnet sensor, i know you've said you've checked them all. I had a similar issue when i was messing with my car, I had bent the bonnet sensor giving the car the impression it was still open, had exact same issue could lock with key but when it comes to the fob it was having none of it. 

 

It was every so slightly bent on straightened the bracket up and its fine. 

I've had the bonnet open & pushed the sensor all the way down while locking the car with the fob, so doubt it's that if anything, but I'll give it another look later.

2 hours ago, Beney86 said:

I actually had a weird issue with the Auto-Vox dash cam mirror, my car would stay in aux mode when i turned the car off- i couldn't lock the car using the key or fob. It would just beep at me, sometimes being a 5 second long solid beep. after about 1-2 mins of being away from the car i could then lock it. After about 3 months of this issue thinking it was wifi signals or a sensor problem with my car.I changed my key fob battery twice just incase. I finally noticed (i dont know how i didn't before) that the cash cam was not powering down when the car turned off and was drawing signal from the glove box connection. Being able to finally lock the car was due to the dash cam finally powering down. Unplugged the dash cam and never had the issue again. 

Probably completely unrelated to your issue, but maybe someone in the future might come across this

I've got a cam plugged into the glove box cigarette lighter for power, & it takes 10 seconds to power down after the car is turned off, so maybe I'll give timing that a shot.