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BGS 1774@Red Beard what brand 36mm wrench is that? It looks like it says Bas on it?
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BGS 1774@Red Beard what brand 36mm wrench is that? It looks like it says Bas on it?
BGS 1774 | Fan Hub Wrench | for Ford, Opel, GM | 36 mm Amazon product ASIN B001ILECSQ@Red Beard what brand 36mm wrench is that? It looks like it says Bas on it?
Thank you!BGS 1774 | Fan Hub Wrench | for Ford, Opel, GM | 36 mm Amazon product ASIN B001ILECSQ
Thank you!BGS 1774
Sucks for people trying to get parts! But kinda cool that they shut it down regardless of loss of business to celebrate the Holiday. Especially in comparison to America nowadays where stores stay open on Thanksgiving!Ordered mine of 8/4 and must have missed them before they went on vacations on 8/8 - so no movement is expected until 8/15.
Height sensors.There aren't really any other wear items with the AHC to worry about are there?
WTF is right. I was surprised at how easy it was and Impex price made it even mo’ betta. I thought I was screwed and had to dump the system. Or pay big bucks to have the AHC system refreshed.Impex'd my truck yesterday. WTF is all I can say. This is one of the easiest jobs I have ever done on my truck and was $600 shipped for the globes. Yet this task remains a mystery and insurmountable challenge for dealers and indie mechanics everywhere. Hopefully the word gets out. Thanks for the O'Reilly wrench tip @SemperRex here's the kit for others: https://www.oreillyauto.com/detail/...ls-evertough-fan-clutch-wrench-set/ren1/67063
My truck rides so damn good. I can finally use the softest comfort setting, it had become unusable shortly after I bought my truck. Rides so damn good. I guess it should. I installed a new AHC pump last year ($160 on Partsouq) so now I have basically a completely refreshed AHC system for less than OME? Am I reading that right? There aren't really any other wear items with the AHC to worry about are there?
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Nice! Height sensors are probably the next in line for wear items on AHC. Not sure what those run via Impex, but they're spendy from McGeorge or Partsouq. Still less than an OME swap, though!Impex'd my truck yesterday. WTF is all I can say. This is one of the easiest jobs I have ever done on my truck and was $600 shipped for the globes. Yet this task remains a mystery and insurmountable challenge for dealers and indie mechanics everywhere. Hopefully the word gets out. Thanks for the O'Reilly wrench tip @SemperRex here's the kit for others: https://www.oreillyauto.com/detail/...ls-evertough-fan-clutch-wrench-set/ren1/67063
My truck rides so damn good. I can finally use the softest comfort setting, it had become unusable shortly after I bought my truck. Rides so damn good. I guess it should. I installed a new AHC pump last year ($160 on Partsouq) so now I have basically a completely refreshed AHC system for less than OME? Am I reading that right? There aren't really any other wear items with the AHC to worry about are there?
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Nice! Height sensors are probably the next in line for wear items on AHC. Not sure what those run via Impex, but they're spendy from McGeorge or Partsouq. Still less than an OME swap, though!
Impex'd my truck yesterday. WTF is all I can say. This is one of the easiest jobs I have ever done on my truck and was $600 shipped for the globes. Yet this task remains a mystery and insurmountable challenge for dealers and indie mechanics everywhere. Hopefully the word gets out. Thanks for the O'Reilly wrench tip @SemperRex here's the kit for others: https://www.oreillyauto.com/detail/...ls-evertough-fan-clutch-wrench-set/ren1/67063
My truck rides so damn good. I can finally use the softest comfort setting, it had become unusable shortly after I bought my truck. Rides so damn good. I guess it should. I installed a new AHC pump last year ($160 on Partsouq) so now I have basically a completely refreshed AHC system for less than OME? Am I reading that right? There aren't really any other wear items with the AHC to worry about are there?
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Definitely remember maintenance of Height Control Sensors. They are simple potentiometers – basically as invented by Thomas Edison way back around 1875, no modern electronics inside!
Movement of the suspension Upper Control Arm moves a linkage to the Sensor arm outside the sensor. This rotates a shaft and causes tiny brushes inside the sensor to move and create a voltage signal to the Electronic Control Unit (ECU). When the Sensor is healthy, this voltage signal is proportional to the position of the tiny brushes running on a carbon track. The resistance and output voltage then is proportional to the position of the Upper Control Arm and the height of the vehicle at any instant in time. The ECU and the whole of the AHC system and the TEMS system depend on the reliability of this signal.
Great device, simple, robust, reliable. The two Front Sensors live in the wheel arches. The position of the Rear Sensor is slightly better protected but it is still exposed, especially at the electrical connector.
Fast forward through 14 to 22 summers and winters in the life of a LC100/LX470 vehicle -- hot and cold conditions, water, snow, salt on roads, mud, road grit, add in trail miles with sticks and stones thrown up, maybe a few water crossings and perhaps some time on the beach. The linkages become rusty and don’t work so well and/or may break or detach. The wiring loom/harness may be damaged. Moisture finds its way into the Sensor or the electrical connector or both, corrosion starts, electrical resistance may increase, or reduce with a short circuit, or there may be an open circuit. The reliability of the voltage signal signal deteriorates.
Given age and conditions, and as well as the tough environment, these Sensors do ‘wear out’. The tiny brushes constantly move on the carbon track in real time with each and every up-and-down movement of the vehicle in motion. The brushes slowly lose their ‘spring’ and their pressure on the carbon track reduces. Meanwhile, wear patterns develop around the most common brush positions. The voltage signal becomes uneven.
Slowly but surely, the voltage signals become erratic. So does AHC and TEMS behaviour. Or the breakdown of the signal and strange vehicle behaviour may be quite sudden after years of accumulated deterioration.
Consider a situation in which one Sensor is outputting about 2.25 volts to the ECU, which is the correct voltage for “N” height. Another faulty Sensor outputs, say, around 0.45 volts (which is the correct voltage at “LO”), or, instead wrongly outputs about 4.05 volts (which is the correct voltage at "HI").
How does the ECU respond?
There will be no DTC’s in this particular case because the Sensor circuits remain within their operating range of 0.3 volts to 4.7 volts. The “rule” (listed in the FSM) governing sending a DTC has not been breached. (There will be DTC’s if the signal is outside this designed operating range for the Sensor circuit).
However, in the above situation the ECU has a mix of conflicting information. It is unable to determine whether to cause the suspension to auto-adjust to “N” or “LO” or “HI” as selected by the driver. Nor can it auto-adjust its height in motion. The ECU has no knowledge about corrosion or wear inside the Sensor or about a damaged linkage or a faulty connector or harness. The ECU responds only to the voltage signal it receives from the Sensor circuit.
In summary: A DTC related to a Height Control Sensor circuit indicates a definite problem BUT absence of a DTC provides no assurance that all is well with a Height Control Sensor.
In such a situation, the ECU will place the AHC/TEMS system into the FSM-defined ‘fail safe’ mode for this condition. AHC operation is prohibited. Active damping by TEMS is prohibited. The Front and Rear of the vehicle may arrive at different heights.
The point of the story is that the benefits of a healthy AHC and TEMS system are lost easily if Height Control Sensors are forgotten and not maintained and replaced when necessary. Such requirements are no different to, say, brake or steering components or the components of any other major system on the vehicle.
Replacement parts with genuine items from TOYOTA/LEXUS or AISIN is best. Yes – it is easy to find substitutes on the web but IH8MUD stories about these mostly are unhappy ones.
Rust-affected Front Height Control Sensor
View attachment 2758144
Internals of a heavily corroded Height Control Sensor
View attachment 2758145