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Limp Mode? All dash lights come on and truck feels like a bucking bull
Son said the symptoms in the video happened to him in Germany before shipping back to the states. I picked up the truck and drove it without much problems straight to our local Indy. Brake light was on for have the trip but made it without any incident.
Indy said they got very fluctuating measurements of the alternator so they replaced it and the grounding strap.
Picked up the truck and almost immediately started getting the symptoms described by my son and are in the recording. It actually gave a do not drive past 30mhp message. Turned the truck off, restarted and all lights went away for about 1 mile and then the bull ride started again ((Sorry, can't get the video thing to work))
Last edited by cybercop; May 23, 2023 at 10:27 PM.
I dont believe so. The brake light comes on for only two reasons that I know of. Either a brake pad sensor is worn/damaged or the EPB is disabled in some way, then the brake light acts as a backup warning. If the light is a bit random, it is usually a pad sensor.
Okay, the good news is that this isn't really that hard to diagnose or fix. The other news (I won't say "bad") is that you are going to need a diagnostic tool that can calibrate your EAS (Electronic Air Suspension) and I recommend the IIDTool by GAP Diagnostics. It's $500 but will pay for itself umpteen times over.
I am going to bet that your issue is either a bad brake switch (less likely since it tells you not to go over 30mph) or a cross articulation fault due to a faulty height sensor. In the former case you just need to change the brake switch ($20 maybe....$30 these days due to inflation? IDK) and in the latter case you need to change the bad height sensor and re-calibrate the EAS. A height sensor is a couple hundred bucks and the calibration takes 30 min or less....but you need the aforementioned IIDTool.
Does your LR3 have the 4x4 Info screen? If so, it would be instructive to see what it's showing when the fault is active.
Rods push the sensors out of operable range. Frankly I am surprised it raises back up at all. Typically when the truck drops to bump stops, which from what you describe, sounds like it is then the sensors are out of range and the system will not air up. Unless you have strut spacers too? That would maybe prevent the sensors from going past their readable limits.
Either way.. back to needing those dang codes to be certain of anything at all.
I promise Dakota's advice is better than theirs, and mine isn't bad either.
Here is everything I would do, feedback from Dakota welcomed:
1. Buy a GAP Tool
2. Buy new height sensors, probably all 4 since you have the modified rods.
3. Install said height sensors (keep the old ones as spares).
4. Calibrate EAS.
5. Live happily ever after.