Detroit Diesel — Speed Sensor Test
Testing & diagnosis
From a Detroit Diesel service manual — check it applies to your exact model before use.
Procedure
- Move master switch to OFF/RESET.
- Connect DC voltmeter between positive (+) lead (wire 24) and ground (wire 2); expect approximately 8-10 V DC.
- Move master switch to RUN to start the generator set.
- With set running, connect voltmeter negative probe to 0 terminal (wire 16 white); positive probe to wire 24 red; expect approximately 12 V DC.
Tools required
- DC voltmeter Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Approximately 8-10 volts DC static
- Approximately 12 volts DC running
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.