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cumminsdr, Mechanic
Category: Medium and Heavy Trucks
Satisfied Customers: 3690
Experience:  All types of Cummins applications
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With the Peterbuilt there is suppose to be a way to check

Customer Question

With the Peterbuilt there is suppose to be a way to check codes and we need to know how to do it. Any ideas? This is a 2008 peterbuilt 387. Also the speedometer and the cruise quit working and the engine is running rough. Any ideas
Submitted: 2 years ago.
Category: Medium and Heavy Trucks
Expert:  cumminsdr replied 2 years ago.
key on and put cruise switch on hold Acel/decl or set/resume to flash the code out. It should blink @@@ pause @@ [email protected] that would indicate fault 321. You may have a DIAG switch that will flash the code as well. The code will only flash when active. Other than that you will need Cummins Insite to retrieve the fault
Expert:  cumminsdr replied 2 years ago. Read operation manual as i stated
Expert:  cumminsdr replied 2 years ago.
Fault Code: 241
PID: P084
SPN: 84
FMI: 2/2
LAMP: Amber
Wheel-Based Vehicle Speed - Data Erratic, Intermittent or Incorrect. The ECM lost the vehicle speed signal.
Engine speed limited to Maximum Engine Speed without VSS parameter value. Cruise control, Gear-Down Protection, and Road Speed Governor will not work
The vehicle speed sensor senses the speed of the tailshaft gear on the vehicle's transmission. This speed signal is then transmitted to the engine electronic control module (ECM) and converted into a vehicle speed.
The vehicle speed sensor is located in the rear of the vehicle transmission. The trans tone wheel may also be loose causing this fault. and a trans repair shop would be required to replace the tone wheel.
This fault is set active when the ECM loses a vehicle speed signal when other engine conditions indicate the vehicle is moving. The fault can also become active if there is a series of clutch, service brake or throttle movements with no vehicle movement. The fault is set inactive when the ECM receives a vehicle speed signal greater than zero.
Expert:  cumminsdr replied 2 years ago.
Hello just following up. Do you need more assistance?Please don't forget to rate my service.
Expert:  cumminsdr replied 2 years ago.
Please don't forget to rate my service.