LR4 No-Start Issue - Detailed post with Video & Faults - Help!

ocdiscovery said:

Hey DJ, thanks for following up! I just gave it another shot, but no dice. I pressed the brake pedal down to the point I thought it may break. I'm 6.4' 250lbs, I put some serious pressure on it.

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Yup, that's what I thought too. Even though I'm 5'3", I can leg press 600 lbs. It has to literally hit the floor till it can't go any further before pressing the start button.

Hey DJ, quick follow up. Once you got it running, after pushing the pedal to the firewall, were you able to turn it off and immediately start it without issue, or the additional brake pedal pressure? The only other thing is, after multiple attempts, I can get this LR started, without the additional pressure. Thanks again for the follow up.

djkaosone said:

Yup, that's what I thought too. Even though I'm 5'3", I can leg press 600 lbs. It has to literally hit the floor till it can't go any further before pressing the start button.

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ocdiscovery said:

Hey DJ, quick follow up. Once you got it running, after pushing the pedal to the firewall, were you able to turn it off and immediately start it without issue, or the additional brake pedal pressure? The only other thing is, after multiple attempts, I can get this LR started, without the additional pressure. Thanks again for the follow up.

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Initially, yes. As time progressed it got worst and was immobile. I didn't want to drive it ever again. Google, "lr4 hard brakes won't start". There's different solutions where it mentions pressing on the brakes as hard as you can, even in the oem troubleshooting manual.

From there, there isn't a straight answer. For me, my transgender neutral shift juice, "tranny oil", was a 1/2 quart low. Adding the 1/2 quart, it still did it. That's when you need to recalibrate the transfer case to adjust the clutch engagement.

Total SWAG from a fellow Oregonian, but...

Have you checked the battery (or batteries) for whether they're good? And that the connections to them are good?

Hey fellow Oregonian, thanks for reaching out! I did replace the main battery, even though the original tested out ok. All connections are clean and free from corrosion, or any debris for that matter. Secondary battery looks good, but I'm not 100% sure if the voltage has been tested. Local LR said the part was on backorder at the moment.

greiswig said:

Total SWAG from a fellow Oregonian, but...

Have you checked the battery (or batteries) for whether they're good? And that the connections to them are good?

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Mashed that brake pedal to china. Still has the no-start issue. I will check the transmission fluid, for a sanity check.

djkaosone said:

Initially, yes. As time progressed it got worst and was immobile. I didn't want to drive it ever again. Google, "lr4 hard brakes won't start". There's different solutions where it mentions pressing on the brakes as hard as you can, even in the oem troubleshooting manual.

From there, there isn't a straight answer. For me, my transgender neutral shift juice, "tranny oil", was a 1/2 quart low. Adding the 1/2 quart, it still did it. That's when you need to recalibrate the transfer case to adjust the clutch engagement.

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ocdiscovery said:

Mashed that brake pedal to china. Still has the no-start issue. I will check the transmission fluid, for a sanity check.

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Good luck... I've been there and don't wish this for anyone. If you have the IIDTool, you can try to recalibrate the TC.

I had the same issue as you actually which ultimately resulted in a no key fob found error. Then i couldn't start the vehicle at all. It turns out that I had a water leak that was coming in from the rear sharkfin antenna up on the roof glass. Water was getting in and it corroded a cable going into a module that's inside the paneling of the rear of the truck. The body control modules do a check when attempting to start the vehicle and once it sensed corrosion and a weird voltage it threw the car into a frenzy. At first i had issues starting and had to cycle the car a few times. Sometimes once started I would get gearbox faults, suspension faults, charging system faults, etc. Other times the car would start just fine and make a roundtrip with no issue. Over the span of a couple months it ultimately got bad to a point where the car wouldn't recognize my key fob.

Here's the issue i had, but with a range rover. Although i don't think it was my parking aid module. It was another module on that same left side right around the area under the cubby storage in the rear. The interior paneling had to be removed. The fix was just cleaning the corrosion out of the pins, sealing up the antenna leak, and removing the BCM codes via this fancy scan tool i had. This all happened around 46k miles and now its been 6 years/60k miles later and no issue.

As a general matter, write the codes down, then clear them before trying to restart. I believe some codes can prevent certain circuits from operating until they are cleared.

Further to Jlach’s post, I think there is a key not found type code in that list. Couple of other codes look interesting here:

P065C-01 is related to the alternator - mechanical failure. Frequent trouble spot on these trucks. Manual says to check the belt tension, but I’m guessing any problem with the alternator might through this code.

B1479-73 - Power Supply Distribution Box - Actuator stuck closed. I believe this is also called the dual battery junction box, and connects the Eco Start/stop battery to the system. Manual says to check the power supply distribution box circuit for short to ground. Then clear all codes, lock the vehicle, wait two minutes, and restart.

Not sure if any of this helps.

Hey, thanks for the info! That's really interesting, as the very first time this issue happened, was the following day after installing our new license plates. My wife mentioned this initially, and I kind of rolled my eyes and shrugged it off. There was some corrosion on the bolts, ultimately I had to really jockey that rear plate free. In doing so, I wonder if I caused something else to loosen, causing a rear hatch leak. I'll take that rear panel off, inspect, and follow up shortly. On a side note: While I do hope you're right here, I'm not looking forward to a much deserved "I told you so"...

jlach993 said:

I had the same issue as you actually which ultimately resulted in a no key fob found error. Then i couldn't start the vehicle at all. It turns out that I had a water leak that was coming in from the rear sharkfin antenna up on the roof glass. Water was getting in and it corroded a cable going into a module that's inside the paneling of the rear of the truck. The body control modules do a check when attempting to start the vehicle and once it sensed corrosion and a weird voltage it threw the car into a frenzy. At first i had issues starting and had to cycle the car a few times. Sometimes once started I would get gearbox faults, suspension faults, charging system faults, etc. Other times the car would start just fine and make a roundtrip with no issue. Over the span of a couple months it ultimately got bad to a point where the car wouldn't recognize my key fob.

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