Auto Service Professional

FEB 2018

Magazine for the auto service professional

Issue link:

Contents of this Issue


Page 41 of 61

40 | ASP February 2018 Technical sensor. ere will be no advantage in terms of reducing corrosion, and the application of thread lube may result in incorrect torque. All TPMS sensor threaded torque values are based on dry threads. Use of a lubricant can easily result in over-torquing. Tips from JS Products Inc. e following information was provided by JS Products' Michael Christopherson. Toyota and Lexus Toyota and Lexus vehicles commonly have a sensor in the spare that will trigger a TPMS light. Always check the spare when looking for a source for the warning light. Toyota and Lexus vehicles may have a Set 1 and Set 2 button. is is so customers can run winter tires. Sometimes the button is pushed by mistake, generating a code. It may be neces- sary to push the switch to turn the TPMS light off. On Toyota and Lexus vehicles there is commonly a "set" button that reassigns the tire positions when tire/wheel assemblies are rotated. If a new sensor is added to the system and the button is pushed before a scan tool relearn process, it will lock the system. e system will need to be unlocked with a scan tool and relearned with a scan tool before the system will operate normally again. In the case of a Set 1 and Set 2 system, the system will need to be relearned twice...once for Set 1 and once for Set 2, including the spare. If tire/wheel assem- blies are taken from a different year of a similar model vehicle, improper sensors may learn to the vehicle, but may report the wrong tire pressure. Correct sensors must be installed. For program- mable sensors, the correct year, make and model must be input. Some aftermarket programmable sensors "lock" after the tire has been inflated. It is important to program the sensor before installing the sensor to the rim. After airing up and installation, the relearn process can be followed normally. Many technicians get confused as to the difference between "programming" and "relearning" the TPMS sensors. Programming is when a programmable sensor is assigned a protocol and ID previous to installation. Relearning is a process of the vehicle system recognizing the IDs and the positions of each wheel. Ford Newer Ford vehicles can be manually learned or they may auto-learn wheel posi- tions. With auto-learn, the wheels may learn to the wrong locations. is is especially true with aftermarket sensors. A best practice is to manually learn wheel positions. Kia and Hyundai Before installing programmable sensors in Kia and Hyundai vehicles, verify that the sensor is applicable to the system, as there are High Line and Low Line systems. High If you're under the assumption that an aluminum TPMS valve stem can't be damaged by over-tightening a cap, think again. Here's an example. Photo courtesy Dill

Articles in this issue

Archives of this issue

view archives of Auto Service Professional - FEB 2018