Dead after remote start, battery fine (1 Viewer)

[BigMF]

So, I installed a remote start kit last year that has worked fine since install. It is configured like most Toyota/Lexus systems in that after you do the remote start the engine stops and you have to restart upon entering the vehicle.

This morning I used the remote start and it started up fine. However, when I got in the truck the whole electrical system shut down. No dash lights, no headlights, no seat adjustments, no beeping when loading the buttons on the fob, no interior lights, nothing. Checked the voltage on the battery and it seems fine at 12.2v. Removed the negative (because it’s easier than positive) wire from the battery for 30 seconds and reconnected. Still no joy. A few minutes later things came back to life. Dash boats lights, seat adjustments, etc. However, when I pushed the start button, I heard a popping/clicking noise from the engine bay and the whole thing went dead again.

Had to run an errand (in wife’s highlander) so I haven’t had a chance to reproduce the effect with her pushing the button so I could listen for the sound.

Any ideas or suggestions for this kind of behavior? First thought is the remote start kit but not sure why it would shut the whole truck down for a few minutes and then mysteriously come back to life.

 

[gaijin]

So, I installed a remote start kit last year that has worked fine since install. It is configured like most Toyota/Lexus systems in that after you do the remote start the engine stops and you have to restart upon entering the vehicle.

This morning I used the remote start and it started up fine. However, when I got in the truck the whole electrical system shut down. No dash lights, no headlights, no seat adjustments, no beeping when loading the buttons on the fob, no interior lights, nothing. Checked the voltage on the battery and it seems fine at 12.2v. Removed the negative (because it’s easier than positive) wire from the battery for 30 seconds and reconnected. Still no joy. A few minutes later things came back to life. Dash boats lights, seat adjustments, etc. However, when I pushed the start button, I heard a popping/clicking noise from the engine bay and the whole thing went dead again.

Had to run an errand (in wife’s highlander) so I haven’t had a chance to reproduce the effect with her pushing the button so I could listen for the sound.

Any ideas or suggestions for this kind of behavior? First thought is the remote start kit but not sure why it would shut the whole truck down for a few minutes and then mysteriously come back to life.

Based on this from Advance Auto Parts:

WHAT IS THE IDEAL CAR BATTERY VOLTAGE YOU CAN HAVE?
Measuring your car battery’s voltage can be a great way to determine how charged your battery might be. The ideal car battery voltage range will provide you with a relevant interval according to which you can measure precisely what the voltage says about the battery’s current charge. A perfect voltage with the engine running is between 13.7 and 14.7V. With the engine off, you should get a reading of 12.6 volts. If the battery isn’t fully charged, it will diminish to 12.4V at 75%, 12V when it’s only operating at 25%, and down to 11.9V when it’s completely discharged. This data and the way it relates to the design of your battery should provide you with some useful insight into the functioning capacity of your car battery.

It sounds like the 12.2V you measured is too low - at least not fully charged at somewhere around 50%.

I have no idea how your aftermarket remote start is wired, so my prime suspect for your symptoms is a bad battery. If it measures 12.2V with no load, it may very well be a symptom of much lower voltage when under load. Time for a new battery?

HTH

 

[TeCKis300]

Based on symptoms, I'm not sure it's related to the remote start at all.

12.2V might be a tad low as it's just been started and the alternator should have been putting electrons back (faulty connection per below may have prevented that). But it's high enough of state of charge (SOC) to start a vehicle. And definitely high enough to keep the lights on.

It sounds like a bad battery connection. You'll want to check the ground and positive cables.
- Make sure the connection are tight with no corrosion. If there is, remove the connection, clean the surfaces, and reconnect
- Check the ground cable at where it secures onto the inner fender. Make sure that connection is tight
- Use your voltmeter in continuity mode. Probe different legs/nodes of the wiring connections to make sure there is continuity

Do you have any non-standard OEM connectors or terminals? They would be the first suspects.

 

[Sandroad]

A battery under even light load (like the electronics with the vehicle off) will have a lower voltage reading. The 12.2V is reasonable. However, I agree with @gaijin a good place to start is a new battery (pun not intended). Those symptoms sound like a possibly failing battery (with a short) and I'm always an advocate for doing the simple things first.

Edit, oops, I see from @TeCKis300 I forgot about battery connections...........that would actually be the simple thing first!

 

[BigMF]

Thanks for the replies guys!

So, removed and cleaned positive terminal connector. A little corporation but really not that bad. When I reconnected it, a pumping noise fired up near the brake cylinder for a few seconds. Got back in and dash lights back on. Tried starting and it struggled for a millisecond and then started up. Voltage was 13.99.

Let it run for a minute, turned it back off and started right up the second time. There is a flashing light on the dash though when the truck is off and is unlocked. When locked the light remains on continuously. The manual does not list anything I can find about the light.

i thought it might be the fob and tried the other fob. Same results and truck starts up fine but the new dash light remains.

Tried remote start and it works fine as well.

So, since I was literally chatting with @TeCKis300 a day or two ago about a new battery I think I’ll go ahead and pull the plug on that. I’ll probably go ahead and pull the plug on new batteries for the fobs as well.

Any other thoughts would be appreciated, especially about the mysterious dash light.

Also @Sandroad, I was thinking there might be simpler (and cheaper ) things to try first as well.

 

[BigMF]

One more thought upon further googling. Is it possible that the remote start caused some kind of issue that caused the alarm to trigger an "immobilization"? A few threads over on ClubLexus that are not specific to the LX 570 suggest that the blinking light may indicate it's in "programming mode" or something.

 

[TN LX570]

When it was totally dead, did you try physically touching the fob to the start button by chance. Mine has been quirky a couple of times and that has resolved it.

 

[TeCKis300]

The flashing security key light is normal and you probably just didn't notice it before.

The relation to your issue today is potentially coincidence or due to the techs installing the autostart disconnecting your battery. And they didn't do a good job of putting it back?

Note that the first start after reconnecting batts always results in a immediate stall. That behavior is normal too. Starts after that should be golden.

 

[BigMF]

Well, the "tech" (myself ) installed the remote start nearly a year ago and the battery has been disconnected many times since. Right now I'm leaning towards

1. Some combination of the battery going bad and slightly corroded connections
2. The bad connection coincidentally happening while the vehicle was in "remote start mode" possibly caused an immobilization that wasn't cleared until disconnecting power completely

Since there was a flurry of activity in the engine bay as soon as I cleaned and reconnected I'm convinced there was something "mechanical" causing the problem and not necessarily "computer/programming" related because it was as if the power was completely disconnected. I did NOT try the key fob next to the start button but thinking that since there appeared to be literally ZERO power to any devices it would not have made any difference.

All that being said, I'm going to go ahead and eliminate the battery as the problem and possibly the fob batteries as well.

Does anyone know if the fobs will need to be re-programmed after replacing their batteries?

 

[gaijin]

Does anyone know if the fobs will need to be re-programmed after replacing their batteries?

No reprogramming necessary - old batt out, new batt in