Deutz-Fahr I25 – Instrument Panel (DIGITEK) / Dashboard ECU: Power output 0 short circuit to battery

The control unit has detected that the preheating control relay (designated as RL42) is short-circuiting to the battery positive (Vcc).

• Agroplus 310, 320, 410, and 420 Profiline series tractors
• Deutz-Fahr Agrofarm series (85, 100, 410, 420, 430)
• Deutz-Fahr 5000 Series (L11)
• Deutz-Fahr Agrotron series
• SAME Explorer 90 / Virtus models

1. 1

   Visually inspect contacts on connector '5K' (at the instrument panel) and connector 'RL42' (at the preheating control relay) to ensure they are firmly secured and not oxidized.

2. 2

   Perform a continuity test with the starter key OFF: disconnect connector '5K' and measure resistance between pin 2 of connector 'RL42' and pin 19 of connector '5K' (should be 0 Ohms).

3. 3

   Test the preheating control relay independently to ensure it is not internally shorted to battery voltage.

4. 4

   Inspect the wiring harness between the instrument panel and the relay for any chafing or melted insulation that could cause a short to a 12V+ source.

1. 1

   Disconnect Battery

   Always disconnect the negative battery terminal before performing electrical repairs to prevent further shorting.

2. 2

   Clean Contacts

   If oxidation was found during the diagnostic checks on connector 5K or RL42, clean the pins with electrical contact cleaner and apply dielectric grease.

3. 3

   Repair Wiring

   If the continuity test fails or a short to battery positive is found in the harness between pin 19 (5K) and pin 2 (RL42), repair or splice the damaged section of the wiring harness.

4. 4

   Replace Relay

   If the wiring is intact but the relay is internally shorted, replace the preheating control relay (RL42).

5. 5

   Clear Codes

   Reconnect the battery. Clear all alarms using the SERDIA diagnostic software/tool, or cycle the starter key first to 'O' (OFF) and then to 'I' (ON) to verify if the alarm returns.