What is CID 990 & How to Solve It?

What is CID 990:

cid 990 indicates a fault with the throttle actuator control circuit. the ecm detects that the actuator is not responding as commanded, resulting in limited throttle response or limp mode.

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Why This Happens:

• faulty throttle actuator motor.
  
• worn throttle body gears.
  
• shorted wiring harness.
  
• ecm calibration issue.
  
• connector corrosion.
  
  

How to Fix It:

1. inspect throttle actuator housing for binding or dirt.
   
2. test actuator motor voltage.
   
3. repair or replace damaged harness sections.
   
4. reprogram ecm throttle calibration.
   
5. replace throttle actuator if it fails tests.
   
   

How to Avoid It Before It Happens:

• clean throttle body and actuator during maintenance.
  
• inspect connectors and harness routing.
  
• monitor throttle response through diagnostics.
  
• clue’s construction fleet management software tracks throttle performance to maintain smooth equipment operation.