Discussion:
code 8l and 4c

I get code 8L and 4C on my truck. sometimes its just 8L as soon as I turn it on and sometimes its that and 4c as soon as I hit the pedal. I have already replaced the dead man switch and cleaned everything up. sometimes it'll go hours without doing it and then it'll do it non stop. any suggestions? if I turn it on and don't touch anything for about 2 minutes 8L will also pop up if it already hasn't
  • Posted 27 Oct 2016 06:31
  • By DanMc
  • joined 8 Jun'16 - 80 messages
  • New York, United States
Showing items 1 - 5 of 5 results.
Hi yes is truly the wire from brake coil was broken 8l pup up.. and revolves the code
  • Posted 13 Sep 2023 04:13
  • By armando_g
  • joined 11 May'18 - 48 messages
  • California, United States
grgarryciencia@aol.com
Look real close at the board female terminals where the relays plug in. Have all relays out, compare each set of female terminals to the others. One set even slightly spread apart, will cause you all kinds of headaches
8L with 4C is always caused by burned relay terminals. Adding just a new relay helps for a bit, then, it fails again
8L by itself is broken wire at brake #1 cause, then relay bad, or pin at VM is burned. You can save the VM by simply jumping the connection from the harness into the VM...Save a lot of mula!
  • Posted 14 Dec 2016 14:09
  • By EasiTek
  • joined 12 Aug'08 - 533 messages
  • Ontario, Canada
Ended up being the k2 relay I replaced was also bad. Sent me in circles because I believed that since I replaced it and the board looked good my problem was elsewhere.
  • Posted 28 Oct 2016 04:28
  • By DanMc
  • joined 8 Jun'16 - 80 messages
  • New York, United States
even if I unplug the switch and leave it open it still gets the 8lwhen I turn it on and stay off the pedal
  • Posted 28 Oct 2016 00:22
  • By DanMc
  • joined 8 Jun'16 - 80 messages
  • New York, United States
wires to dead man switch go open, short harness
check previous 7400 posts
  • Posted 27 Oct 2016 11:29
  • By EasiTek
  • joined 12 Aug'08 - 533 messages
  • Ontario, Canada

Post your Reply

Forkliftaction accepts no responsibility for forum content and requires forum participants to adhere to our rules of conduct. Click here for more information.

If you are having trouble using the Discussion Forums, please contact us for help.

Fact of the week
The two internal cavities in our nose called nostrils function as separate organs. Each nostril has its own set of turbinates and olfactory receptors. The two independent organs work together through a mechanism called the nasal cycle, where one nostril is dominant for air intake while the other rests and is better at detecting scents.
Upcoming industry events …
March 3-7, 2026 - Las Vegas, NV, United States
January 28-30, 2026 - Bangkok, Thailand
31 March 2026 - Dubai, United Arab Emirates
Latest job alerts …
Bensenville, United States
Monmouth, IL, United States
Bensenville, United States
Movers & Shakers
James Brown James Brown
Chief operating officer, Bulldog Battery Corporation
Commercial excellence roll-out manager, TVH Parts
President EPG Americas, Ehrhardt Partner Group (EPG)
CEO, Duravant