1998 5.2L dead after trying to jump start code 920 921 and 999 along with dead dash
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1998 5.2L dead after trying to jump start code 920 921 and 999 along with dead dash
So I killed the battery by leaving the dome light on. I went to jump start it and it wouldn't start even after fully charging the battery. I was also getting no OBD signal to my scanner from the port and my dash was dead with the odometer blinking and displaying the codes 920, 921 and 999, but note I wasn't getting the NO BUS warning. So after much research I decided that the PCM was probably toast. I replaced it with an Ebay junk yard unit. Unit arrives and the truck starts but the dash still doesn't work with the same odometer codes. So after more research I tried replacing the CTM and the dash, same result, dead dash but truck runs. Contacted the PCM seller and told him my story and he reluctantly sent a new PCM. Installed the new one and now everything works. This is a FYI as to what your problem could be.
Last edited by hippy288; Jan 1, 2021 at 08:26 PM.
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So I killed the battery by leaving the dome light on. I went to jump start it and it wouldn't start even after fully charging the battery. I was also getting no OBD signal to my scanner from the port and my dash was dead with the odometer blinking and displaying the codes 920, 921 and 999, but note I wasn't getting the NO BUS warning. So after much research I decided that the BCM was probably toast. I replaced it with an Ebay junk yard unit. Unit arrives and the truck starts but the dash still doesn't work with the same odometer codes. So after more research I tried replacing the CTM and the dash, same result, dead dash but truck runs. Contacted the PCM seller and told him my story and he reluctantly sent a new PCM. Installed the new one and now everything works. This is a FYI as to what your problem could be.
