Discussion:
No Hydraulic functions

I'm working on a SC4500, just replaced counter balance valve but have no hydraulic function. Pump is not engaging when you sit on the seat. You can't here the pump contactors click. It is a brand new contactor, also replaced the jumper diode. The pump FU2 200amp fuse is good. Seat switch is good. All fuses checked and found good. Any and all advise is very welcomed.
  • Posted 29 Jul 2020 05:13
  • By richard_cucuta
  • joined 29 Jul'20 - 3 messages
  • Georgia, United States
RichardCucuta
Showing items 1 - 3 of 3 results.
Check pin 7 and 8 for battery negative on CA631. There may be an option for a tilt interlock which may be a factor in the issue if its equipt. Does the BDI (access1) work properly?
  • Posted 31 Jul 2020 03:12
  • By ForkLiftFred
  • joined 2 Aug'18 - 24 messages
  • New Hampshire, United States
Fix it
The problem was a Bad BDI and a Damaged battery negative wire coming from CA631-07
  • Posted 31 Jul 2020 01:16
  • By richard_cucuta
  • joined 29 Jul'20 - 3 messages
  • Georgia, United States
RichardCucuta
Could you provide a part number for the part you replaced? Was this the original issue or was this an issue that began after replacing the part? Seat switch is plugged in? Fuse for the circuit is good? Seat switch normally runs steer motor for a few seconds then shuts off, does that run? Does the lift beep at you when you attempt to use the hydraulic levers? Does it travel? Apologies for so many questions trying to get an idea where to start.
  • Posted 30 Jul 2020 23:25
  • By ForkLiftFred
  • joined 2 Aug'18 - 24 messages
  • New Hampshire, United States
Fix it

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.

Upcoming industry events …
October 6-9, 2025 - Detroit, MI, United States
October 6-9, 2025 - Detroit, MI, United States
November 14, 2025 - Melbourne, Australia
Global Industry News
edition #1237 - 3 July 2025
While innovation and new technology are evolving at what seems to be an ever-increasing pace, the need to capture the data (telemetry) from this tech, and the ability to utilise it (telematics) for efficiency and cost savings, is one area attracting more and more attention ... Continue reading
Global Industry News
edition #1237 - 3 July 2025
While innovation and new technology are evolving at what seems to be an ever-increasing pace, the need to capture the data (telemetry) from this tech, and the ability to utilise it (telematics) for efficiency and cost savings, is one area attracting more and more attention ... Continue reading
Fact of the week
The use of "hello" as a telephone greeting is attributed to Thomas Edison. He is said to have suggested it as a simpler alternative to other greetings, such as "Do I get you?" or "Are you there?".

PREMIUM business

Tailift Material Handling Taiwan Co.,Ltd.
Focused simply for the new era.
Movers & Shakers
Jeannette Walker Jeannette Walker
CEO, MHEDA
President, European Rental Association (ERA)
Chief marketing officer, JLT Mobile Computers
Chief executive officer, East Penn Manufacturing