If you are having trouble getting the seatbelts in your older Dodge Ram to extend enough to put them on, this video is for you.
This video is a deep dive into the seatbelt control timer module design in the 1998-2001 Dodge Ram. This iteration of the Ram had the seatbelt spool built into the seat back rather the B pillar of the cab. With this design, rear passengers could enter and exit the vehicle without having to sweep the front seat belt strap out of the way. So rather than using a pendulum device that might be problematic with variance in seat angle, they designed an electronic timer module to unlock seat belts.
Ultimately that design was problematic for various warranty callbacks, so Chrysler abandoned the design after 2001. They no longer make this module, and with the small number of vehicles still on the road, aftermarket companies don’t make one, either.
This video explores how this circuit is designed, it discusses various repair options, and it shows a general game plan for assessing dysfunctional automotive modules.
All automotive repairs involve risk, so a wise back yard mechanic needs to asses his own skill set when deciding whether to proceed. The information contained here is largely taken from the Chrysler dealers repair manual, but there are no guarantees as to safety or accuracy. Any misadventure you encounter if you decide to move forward with DIY repair is on you.
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Have You tried trick with a cigarette lighter ?
interesting nice explanation
Thank you again!
Eric O. reminds us to understand the theory of operation before you begin the diagnosis. What is the NORMAL logic for this timer? I'm hoping that if your battery dies then you're not trapped? And that you can adjust your belt with the door closed? Was this ABNORMAL behaviour, such as the inertial ball getting stuck? Or the timer not counting down? Or both combined?
What if a door switch breaks?
I suspect the designers feared the danger of airbag deployment and demanded a redundant seat belt, i.e. electrical + centrifugal. EDIT: Just saw your comment about this being an electronic relocation of the pendulum device.
I have owned the same truck since new. I had this problem about 15 years ago. I found that if I unplugged the module it would work again. The intermittent failures became more frequent and more annoying so I checked powers and grounds, condemned the module, and took a ride to the local (at the time) U-Pull-It. For a whopping $7! I had a used module, installed it, and it's worked ever since. So nice not having to reprogram simple things like this. I still have that old non working module somewhere and that truck is still my daily driver!
Great video. If new modules are no longer available, another option would be to split the case on your module and see if there is anything obvious like a cold solder joint or something that may be simple to fix. I would guess that given the age of the truck and the fact that it is delivering battery voltage to the solenoids the driver is not an obscure or custom chip. It may something as simple as a solid state relay. If it is not easily repairable, you always could revert to the blue jumper fix.
You have a great way of explaining things. You're very detailed and complete in your process too. Great tutorial.