Help! 2006 LX470 starts but won’t shift from park. Gauges/ head unit dead as well.

[Stephen Lugo]

Friends,

2006 lx470
1.Left at JFK long term parking for 2 weeks.
2.Multiple heavy rains during storage
3.Upon return vehicle starts fine.
4. During drive I hear clicking under driver dash and gauges & head unit turn off. Vehicle makes it home.
5. Next day drive for coffee and park. Vehicle starts but is locked in park. No head unit, no ac, no power windows or side mirrors. I over ride shifter & drive home.
6. Check/clean all grounds under hood. Check all 3 fuse locations and fuses. Clean battery terminals.
7. Vehicle then does not start and starter just clicks.
8. Test 6month old battery to find low voltage.
9. Buy/install new 27f battery.
10. Vehicle starts and head unit & dash come alive.
11. Hear clicking under drivers dash and head unit & gauges go out.
12. Now, pressing unlock on key fob prompts a chirp from the alarm but no lock motion. Lock button does not prompt any chirp or locking action.
13. Tested new battery and it is producing just over 12v on a hand held tester.
* while vehicle is running gauges are dead, but brake, vgrs, abs, vcs lights are on.

I tried to chronicle the events to be as clear as possible. I’m in a bind cause here in Brooklyn the vehicle has to be moved multiple times per week for alt side parking.

 

[khymel5]

My first instinct would be water ingress causing damage to one of your junction blocks or computers. A common problem with the 100 series is a leaking windshield seal. Do you know if your 100 has the original windshield, or if its been replaced at some point? Improper replacements are frequent, and this usually causes water ingress issues. Another common issue is clogged sunroof drains. These both result in water coming in somewhere around the A pillar, and leaking down onto various electronics.

Here's something to try: pull the trim off both A pillars by prying off the screw covers on the grab handles and removing the phillips head screws. Remove the handles and the trim will lift up and out. Then, get a hose or something and spray water around your windshield seal. Also, open your sunroof and carefully pour some water into the drains in the front part of the channel. The water should drain out under the vehicle quickly after pouring. After thoroughly spraying for a while, go inside and inspect the interior of the A pillars for any water ingress. Then look at the driver and passenger footwells for any signs of water. Then, lay down and look up into the dash for any signs of water.

 

[khymel5]

Here are some pictures from the electrical wiring diagram to get you started, I highlighted some areas of interest.

 

[Stephen Lugo]

Here are some pictures from the electrical wiring diagram to get you started, I highlighted some areas of interest.
View attachment 2059868
View attachment 2059869

Thank you! I just did what you recommended. Took off the a pillar molding under the front handle and sprayed windshield with the hose for a while. No water infiltration that I can see. I can’t clear the sunroof drains as the sunroof is inoperable along with my windows, locks and head unit.
I tested the new battery and it came in at a little over 12v. Same reading it was giving me while the vehicle was running. Could that be the reason for my issues. Vehicle starts , but can’t shift out of park.

 

[khymel5]

Hey Stephen,

Most of the problems you mentioned have fuses in the driver's side interior junction box, also known as the kick panel fusebox, or "Cowl Side J/B LH" in the factory service manual. Could you double check the 7.5A ACC and AM1 fuses, the 10A ECU-IG1 and 10A GAUGE1 fuses there? There's also a 25A DOOR and SUN ROOF fuse there.

Do the following still work? Headlight, taillight, horn, interior lights, power windows, power locks from interior buttons, power tilt steering wheel, power seat adjustment, power antenna, turn signals, radio, windshield wiper? I know this sounds tedious, but these are all fused through different junction blocks, and knowing which ones are still operating can help narrow down the problem.

What's the battery voltage while idling?

Also, here's a link to download the factory service manual. The EWD section will probably be very helpful.

 

[Stephen Lugo]

Hey Stephen,

Most of the problems you mentioned have fuses in the driver's side interior junction box, also known as the kick panel fusebox, or "Cowl Side J/B LH" in the factory service manual. Could you double check the 7.5A ACC and AM1 fuses, the 10A ECU-IG1 and 10A GAUGE1 fuses there? There's also a 25A DOOR and SUN ROOF fuse there.

Do the following still work? Headlight, taillight, horn, interior lights, power windows, power locks from interior buttons, power tilt steering wheel, power seat adjustment, power antenna, turn signals, radio, windshield wiper? I know this sounds tedious, but these are all fused through different junction blocks, and knowing which ones are still operating can help narrow down the problem.

What's the battery voltage while idling?

Also, here's a link to download the factory service manual. The EWD section will probably be very helpful.

Checked all of the items you outlined. As it stands now the vehicle starts and runs. No ability to shift, no power to gauges, no windows or locks or head unit. Yesterday everything worked for a moment and then I heard a distinct click under the driver side dash. Then everything went off. Is there a specific relay under there that could be the culprit?

 

[playdrv4me]

Following, this is quite an interesting mystery. Free bump for you.

 

[khymel5]

Hey Stephen,

The relays are on the back of the junction box, they're very hard to access. The clicking you hear is probably one of the relays, although if it's clicking, that likely means it isn't the problem. Is it possible for you to get a blower to dry out any potential moisture in that area? I know you said you're street parked, so that's probably not possible.

I would also still like to hear whether headlights, taillights, interior lights, turns signals, and horn are functional.

 

[jerryb]

and running voltage, or maybe you did say it was same 12.xx running or not running?

 

[Stephen Lugo]

and running voltage, or maybe you did say it was same 12.xx running or not running?

Running voltage is 12.13. Resting voltage is 12.29.
Battery is brand new sears gold 27f. Took it out this afternoon and brought it back to sear where they tested it as good 12.4 volts.

 

[Stephen Lugo]

Hey Stephen,

The relays are on the back of the junction box, they're very hard to access. The clicking you hear is probably one of the relays, although if it's clicking, that likely means it isn't the problem. Is it possible for you to get a blower to dry out any potential moisture in that area? I know you said you're street parked, so that's probably not possible.

I would also still like to hear whether headlights, taillights, interior lights, turns signals, and horn are functional.

Has not rained in a few days and when I got up in the kick panel it seemed quite dry. Headlights work. No signal lights. Interior lights work. Alarm chirps when unlock is pressed and does not respond when hitting lock button. Btw, only chirp no unlocking action.

 

[khymel5]

Running voltage is 12.13. Resting voltage is 12.29.
Battery is brand new sears gold 27f. Took it out this afternoon and brought it back to sear where they tested it as good 12.4 volts.

A running voltage of 12.13 is way too low, that sounds like we're getting closer to the root cause of your problems. Voltage while idling should be above 13.5, ideally above 14. Low voltage does all sorts of weird things on the 100 series. Although I can't imagine that a bad alternator could be causing problems for you when the truck isn't running.

 

[playdrv4me]

A running voltage of 12.13 is way too low, that sounds like we're getting closer to the root cause of your problems. Voltage while idling should be above 13.5, ideally above 14. Low voltage does all sorts of weird things on the 100 series. Although I can't imagine that a bad alternator could be causing problems for you when the truck isn't running.

I had the same thought. Sounds like you're having some charging system issues. I suspect that putting the new battery in gave you just enough voltage to keep things running for a bit, then that battery ran down enough to start your problems all over again.

 

[Stephen Lugo]

Do I need to try a different battery? Otherwise how would one diagnose a bad alternator?

 

[khymel5]

Do I need to try a different battery? Otherwise how would one diagnose a bad alternator?

The FSM spec for engine off battery voltage is 12.5 to 12.9, for idling voltage it's 13.2 to 14.8, so you're low on both specs. When you first installed this new battery, did you turn the key to the ON position without starting and see if everything worked like it should?

 

[OEMGUY0720]

Rule out the battery by using or borrowing a known good battery of the same size and spec as you have now.

 

[Mauk1]

I just posted on how a windshield leak led to the total loss of my 07. You can try and run it through a car wash, then pull the carpet back by the corners and feel it there's water.

 

[Vermont]

Sounds like you're having some charging system issues. I suspect that putting the new battery in gave you just enough voltage to keep things running for a bit, then that battery ran down enough to start your problems all over again.

This has my vote for the culprit.

 

[Stephen Lugo]

This has my vote for the culprit.

Well !
Last night I decided to start the vehicle and wiggle any visible wire under the hood. I don’t want to believe it’s my alternator. So when I wiggled the wire terminal just off the positive post, the gauges and head unit came alive. Turned off the vehicle ,but when I restarted it to test the change it went back to no power to accessories. Cleaned junction post terminal. Then wiggled the part of the loom that runs on top of the radiator and Bam! Got full power again. Btw ,the battery measured great output in the dash and meter. Anybody experience this?

 

[khymel5]

It sounds like you're very close to figuring this out. If I were you, I would tape/clamp down my voltmeter leads to the battery, start the engine, then experiment with jiggling different parts of that wire while watching the voltmeter. Try to find a spot that causes the voltage to jump up to the 13.5+ range.