When testing the Ignition Off Draw as at page 8A-10, the manual states that after 3 minutes this should reduce to max 25 ma. However, page 8M-14 states that the seatbelt ratractor latches only de-energise after 30 minutes. On my truck, this gave a 400 ma draw for 30 minutes. This is important if you're trying to trace the cause of flat batteries, as I was. Nick
This came to light when I attempted to trace the source of an Ignition-Off Draw (IOD) of 400 ma instead of the maximum of 25 ma after waiting 3 minutes, as stated in the manual at pages 8A-10 and 11. This was in connection with a flat battery problem, which eventually turned out to be a defective battery. I found the IOD reduced to zero when the IOD fuse (12) was removed, so I went to page 8w-12-12, and attempted to isaolate one by one the 14 items supplied by this IOD fuse. Eventually, by disconnecting the loom under the driver's seat, I found the drain to be from the Seatbelt Control Module. I then went to page 8M-13, to read and understand the Seatbelt Control Timer Module (SCTM). I read at page 8M-14 that the retractor latch solenoids are only de-energised after 30 minutes!! I repeated the IOD test, with the doors closed, and waited 30 minutes, at which time the IOD reduced to zero! The truck is perfect, but the IOD test page says 3 minutes. I wasted a morning on this. If we had a thread or forum called "98 Service Manual Notes" or similar, any person buying a manual could run through all the posts, make notes on the pages of things of interest, and perhaps save a lot of aggravation and time. There is a huge amount of knowledge amongst you all, and sharing it in this way might prevent newbies like me repeating errors that have already been detected by others.
This came to light when I attempted to trace the source of an Ignition-Off Draw (IOD) of 400 ma instead of the maximum of 25 ma after waiting 3 minutes, as stated in the manual at pages 8A-10 and 11. This was in connection with a flat battery problem, which eventually turned out to be a defective battery. I found the IOD reduced to zero when the IOD fuse (12) was removed, so I went to page 8w-12-12, and attempted to isaolate one by one the 14 items supplied by this IOD fuse. Eventually, by disconnecting the loom under the driver's seat, I found the drain to be from the Seatbelt Control Module. I then went to page 8M-13, to read and understand the Seatbelt Control Timer Module (SCTM). I read at page 8M-14 that the retractor latch solenoids are only de-energised after 30 minutes!! I repeated the IOD test, with the doors closed, and waited 30 minutes, at which time the IOD reduced to zero! The truck is perfect, but the IOD test page says 3 minutes. I wasted a morning on this. If we had a thread or forum called "98 Service Manual Notes" or similar, any person buying a manual could run through all the posts, make notes on the pages of things of interest, and perhaps save a lot of aggravation and time. There is a huge amount of knowledge amongst you all, and sharing it in this way might prevent newbies like me repeating errors that have already been detected by others.
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