Recently while driving a 4th gen 2015 Ram 2500, the TPMS light was on when the tires were displaying 71 PSI for the rear tires and 62 PSI for the front tires. The car’s computer highlighted only the right rear tire and asked to fill to 80 PSI. When driving in colder or warmer months, it can be hard to get your tires exactly where the pre-set thresholds on the TPMS are programmed. By default, the Ram 2500 is programmed to 60 PSI in the front and 80 PSI in the rear. This can make for a bumpy ride when you aren’t towing.
Changing the TPMS thresholds on the truck use to be something the dealer could do, but the ability has been removed from their programmers. To change your thresholds, many people recommend buying a $1,000+ Autel Maxisys MS906 programming device. It works by changing the thresholds, and then syncing those new thresholds with the wireless TPMS settings. This scan tool will do almost anything you can think of on any brand vehicle. However, I was looking for the cheapest way to change these TPMS thresholds for the much cheaper.
Cheaper Route: Bluetooth OBD tool + AlfaOBD
Some people found a cheaper route with a $99 OBD plug called OBDLink MX+. Using this OBD plug, you can control almost every system on most vehicles, including ABS and SRS (airbag) systems. If you have the budget, that is the recommended OBD plug to have in your toolbox. Using that plug and the AlfaOBD Android app (sorry, no iPhone – you could try a $20-30 Android phone like the LG Rebel), you are able to change your Ram’s TPMS threshold at home. Many people recommend the OBDLink MX+ over the similarly priced $99 BlueDriver OBD tool as the OBDLink MX+ tool has greater compatibility with a wider range of advanced functions, vehicles, and phone apps.
Cheapest Route: BAFX OBD Tool + AlfaOBD
If you’re looking for the cheapest route of $20.99 (as of December 2020), you can use the BAFX OBD scan tool. For some reason, I had a hard time confirming on the forums if this cheaper OBD tool will accomplish reprogramming a 4th gen Ram TPMS thresholds. After trying it, I can confirm it has worked! The BAFX OBD tool is supposed to only get into the body computer and TPMS modules for the Ram, but that is all we need for this procedure. It will also read your check engine codes, and many other things, but if you’re looking for ABS and SRS, you’ll probably not have success according to their product description page.
Additionally, there are 2 more requirements:
Android phone with AlfaOBD app (not Demo version). The full version is $49 on the Google Play store. If you want to try AlfaOBD without paying, search google for “AlfaOBD apk”, you can decide if you want to download it from an alternative site. Just make sure to scan the apk with VirusTotal before installing it. Better yet, always use a spare donor phone you’re no longer using that doesn’t have valuable info to steal when installing apk’s that aren’t from the Google Play store.
Windows alternative: if you have a laptop with bluetooth, you could also try downloading the AlfaOBD program from their website. To activate the key to allow for full programming functionality, you can pay the $50 activation or google search “AlfaOBD_lic_gen.exe”.
- 4 digit Ram code – you can only get this in person at your local Ram dealer and is specific to your truck’s VIN. You take your driver’s license and truck’s registration to the Parts counter at the dealership to prove ownership, and they will get you your truck’s 4 digit security code to program/sync the wireless TPMS system. They should not charge you for this.
How to Reprogram the 4th gen Ram TPMS Thresholds with AlfaOBD
Once you have the OBD scanner, AlfaOBD, and your 4 digit code, you are ready to reprogram your TPMS thresholds. I performed this programming on a 2015 Ram 2500, but this procedure should would on all 4th gen Ram’s, including 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, and 2018.
- Plug in your OBD reader and turn the truck ignition to the run position (without starting)
- Turn on phone’s bluetooth and connect to OBD reader. Open AlfaOBD and press bluetooth icon, select your OBD reader. To function, I had to allow AlfaOBD permission to access files on my phone.
- Select Ram and your vehicle from the main AlfaOBD menu. Select Body Computer function. Select the Control Unit from the list that matches your year model. You may need to try multiple Body Computer PowerNet options from the Control Unit list if at first it doesn’t work.
- Press red Connect button. Once connected, press car icon in lower right corner with the open hood.
- From “Select procedure to start” menu, choose “Update Pressure Thresholds”. You should then see “Status Pressure Front” and “Status Pressure Rear.” Select the desired PSI that you want the TPMS system to warn you at: example, 40 PSI. Press Start button and wait until completed.
- Press the phone’s back button or key icon to return to the home screen of AlfaOBD. Change the “Body Computer” function option to “Radio Frequency Hub(RFH).” Choose the proper Control Unit from the list.
- Press the red Connect button. Once connected, press icon in lower right corner with open hood.
- From “Select procedure to start” menu, choose “RF-HUB Reset/Replace”. Enter the 4 digit PIN the dealer gave you. Press Start button and wait until completed.
- Unplug OBD sensor, turn key to off. Turn truck on and see if your TPMS warning light is gone at desired tire pressures.
Depending on how you acquired AlfaOBD, you should have now reprogrammed your TPMS thresholds on your 4th gen Ram for as low as $21!