Fleet Manager Guide
Structured diagnostics reduce shop time, lower repair costs, and keep trucks on the road. This guide shows fleet managers how to use pre-shop diagnostics to cut downtime and improve repair accuracy.
How Fleets Save Money
Eliminate parts cannon repairs
Structured diagnostics identify the root cause before parts are ordered. Fleets that diagnose before ordering reduce unnecessary parts spend by 30–50%.
Reduce shop labor waste
A technician who arrives at the shop with a documented diagnosis and fault code history spends less time diagnosing and more time repairing.
Prevent repeat failures
Understanding root cause prevents the same failure from recurring. A replaced NOx sensor that fails again usually means a DEF quality problem was never addressed.
Prioritize repairs by severity
Not every fault code requires immediate repair. Structured diagnostics help fleet managers prioritize which trucks need immediate attention vs. scheduled maintenance.
Pre-Shop Diagnostics
Before a truck enters the shop, a driver or fleet technician should complete a pre-shop diagnostic. This takes 10–15 minutes and saves hours of shop time.
- 1
Pull all fault codes
Connect a scan tool and record all active, pending, and historical fault codes. Note any active derates.
- 2
Record live data snapshot
Capture DPF soot load, DEF level, boost pressure, fuel rail pressure, and coolant temp at the time of the complaint.
- 3
Document the complaint
Record exactly when the problem occurs — at idle, under load, cold start, hot restart. Specific conditions help the technician reproduce the fault.
- 4
Note recent repairs
List any recent repairs or parts replaced. This prevents duplicate work and helps identify if a previous repair caused the current fault.
- 5
Send the report to the shop
Provide the fault code list, live data snapshot, and complaint description to the shop before the truck arrives. The technician can prepare parts and tools in advance.
Downtime Reduction
Derates are the leading cause of unexpected downtime. Monitor fault codes daily to catch derates before they strand a truck.
DPF soot load above 80% means a forced regen is needed soon. Catching this before it hits 100% prevents a roadside breakdown.
DEF quality faults trigger a 5 mph derate within hours. Check DEF quality and level at every fuel stop.
Intermittent faults are harder to diagnose than active faults. Document when and how often they occur to help the technician reproduce the problem.
Preventive maintenance on fuel filters, air filters, and coolant reduces the frequency of unplanned repairs.
Fleet Reporting
AI Diesel Tech tracks repair history, fault codes, and diagnostic outcomes for every truck in your fleet. Use this data to identify patterns and reduce repeat failures.
Repair History
Every completed diagnosis is logged with fault codes, steps taken, and outcome.
Fault Frequency
See which fault codes repeat most often across your fleet to identify systemic issues.
Technician Consistency
Track diagnostic accuracy and repair outcomes by technician to identify training needs.
Ready to reduce fleet downtime?
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