Xevo TQ-S turbo pumps do not turn on when pumping down - WKB224652

SYMPTOMS

• When selecting pump down on the tune page, the rotary pumps turn on but the turbo pumps do not
• Readbacks for the turbo speed are 0 and do not change
• Cooling fans on the turbos do not power-on

ENVIRONMENT

• Xevo TQ-S

CAUSE

The turbo controllers are not getting a pump down signal from the electronics. Something has latched into an error state and cycling the power does not reset the error state.

FIX or WORKAROUND

1. Close MassLynx and power-down the electronics.
2. Switch the system to pump override and the rotary pumps and turbos should turn on—the turbo cooling fans should also be on.
3. Power-on the electronics and establish communications with MassLynx.
4. When the tune page is opened, turn off the pump override switch and the system should continue to pump down, and the turbo readbacks should now update normally.

ADDITIONAL INFORMATION