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DTC 12 - Rpm Signal

The Integrated Ignition Assembly (IIA) contains 2 pick-up coils ("G" and "NE"). The "G" signals informs ECM of the standard crankshaft position. The "NE" signals informs the ECM of the crankshaft position and engine speed.

If the "NE" signal is not present to ECM within 2 seconds or more after cranking, check for open or short in the "G" or "NE" circuit, or for a faulty IIA.

If "G" signal is not present from ECM for 3 seconds or more with engine speed between 600-4000 RPM, check for open or short in "STA" circuit or for a faulty ECM.

Fig 1: DTC 12 - Schematic
G94A45138Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 2: DTC 12 - Inspection Using Oscilloscope
G93I80034Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 3: DTC 12 - Diagnostic Flowchart
G94B45139Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002