Detroit Diesel — Reading Diagnostic Codes, Flash Method
Testing & diagnosis · DDEC IV diagnostic system
From a Detroit Diesel service manual — check it applies to your exact model before use.
Applies to: Detroit Diesel Series 60 engine
Before you start
- The override switch must be used only in emergency cases; excessive use can cause serious damage to the engine.
Procedure
- Make sure the rear-starting switch located in the engine compartment is in the normal position.
- With the ignition ON and the engine idling or shut off, momentarily depress the Stop Engine Override switch.
- Active codes are flashed on the stop engine telltale, followed by inactive codes flashed on the check-engine telltale; the cycle repeats until the override switch is depressed again.
- A code 43 consists of four flashes, followed by a short pause, then three flashes in quick succession.
- Fault codes can only be cleared using the DDR.
Tools required
- Diagnostic Data Reader (DDR) Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Active codes are flashed in ascending numerical flash code order
- Inactive codes are flashed in most recent to least recent order
Full service-parts list: Detroit Diesel Series 60 engine →
Source: Detroit Diesel service manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.