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For 1990-2009 cars only

Intermittent Crank No Start with DTC P1780 Set in ECM History and/or U2105 Set in TCM or BCM History

Subject:Intermittent Crank No Start with DTC P1780 Set in ECM History and/or U2105 Set in TCM or BCM History (Replace Main V6 Relay in Underhood Fuse Block [UHFB])

Models:All 2000 L-Series Sedans and Wagons built before VIN YY630765 equipped with V6 (RPO L81) engines



Condition

Some customers may comment the engine intermittently cranks but will not start and Service Engine Soon telltale is illuminate.

Cause

The Main V6 Relay in the underhood fuse block (UHFB) intermittently may not function as designed.

Procedure:

Replace the Main V6 Relay using the following procedure.

  1. Disconnect negative battery cable.
  2. Remove underhood fuse block (UHFB) cover.
  3. Remove Main V6 Relay.
  4. Install Main V6 Relay (P/N 12135170)
  5. Install UHFB cover.
  6. Connect negative battery cable.

Tighten
Battery Terminal Bolt: 17N·m (13 lb ft)

Parts Information

PARTS REQUIREMENTS:

12135170 - Relay Asm-Acsry

Claim Information

CLAIM INFORMATION:

To receive credit for this repair during the warranty coverage period, submit a claim through the Saturn Dealer System for J6369 (Relay, ECM [Main V6] - Replace), or if another procedure is performed, refer to the appropriate Electronic Labor Time Guide for the correct labor operation code and time.