61027 Mercruiser GEAR, PINION - DRIVE SHAFT

Sensor Locations
Illustration 1 g06300126
C27 Electronic control system components
(1) Turbocharger inlet temperature sensor for cylinders 1, 3, and 5
(2) Turbocharger inlet temperature sensor for cylinder 7, 9, and 11
(3) Oil level (Engine running add)
(4) Oil level (Engine off full)
(5) Oil level (Engine off OK to start)
(6) Crankshaft speed/timing sensor
(7) Engine oil pressure sensor
Illustration 2 g06300135
C27 Electronic control system components
(8) Electronic Control Module (ECM)
(9) Left intake manifold temperature sensor
(10) Left intake manifold pressure sensor
(11) Coolant temperature sensor
(12) Camshaft speed/timing sensor
(13) Atmospheric pressure sensor
(14) Right intake manifold pressure sensor
(15) Right intake manifold temperature sensor
Illustration 3 g06299879
Right side turbo view
(16) Turbocharger inlet temperature sensor for cylinders 8, 10, and 12
(17) Turbocharger inlet temperature sensor for cylinders 2, 4, and 6Cat Data Link
A Cat data Link is used for the following items:
Communicate engine information.
Communicate with Caterpillar Electronic Technician (ET).
Calibrate the electronic engine control system.
Troubleshoot the electronic engine control system.
Program the electronic engine control system.The Cat Data Link is used to communicate engine information to other electronic control systems. Also, the Cat Data Link can interface with Cat ET.The Cat Data Link monitors engine information. The engine information that is available on the Cat Data Link includes the following information:
Boost pressure
Engine identification
Engine speed
Oil pressure
Status and diagnostic information
Throttle positionCat ET can be used to program the customer specified parameters. The tool is plugged into the connector for the Cat Data Link. This allows Cat ET to communicate with the ECM. Also, Cat ET can be used to display the real-time values of all the information that is available on the Cat Data Link. This action will help diagnose engine problems.Electronic Control Module (ECM)
The engine uses an Electronic Control Module (ECM). The ECM is a microprocessor-based device. The ECM is mounted on the right side of the engine.The inputs and the outputs to the ECM are designed to withstand short circuits without damage to the control module. The electronic engine control system has the following features that are designed into the system.
Resistance to radio frequency
Resistance to electromagnetic interferenceThe system has passed tests for interference by two-way radios and by switching noise.The ECM power supply provides electrical power to all engine-mounted sensors and actuators. The following precautions have been designed into the ECM.
Reverse voltage polarity protection
Power swings or surges of voltage due to sudden alternator loadsThe ECM also monitors all sensor inputs and the ECM provides the correct outputs in addition to acting as a power supply. Also, the ECM ensures the desired engine operation.The ECM is programmed with a selected factory engine rating. The ECM memory contains a personality module identification code. This code is used to avoid unauthorized tampering or switching of personality modules and other pertinent manufacturing information.The wiring harness provides communications to the following areas:
ECM
Various sensors
Cat Data Link
Engine connectorsThe ECM is programmed to perform the following functions:
Diagnostic tests on all inputs
Diagnostic tests on all outputs
Identify a faulty circuit.Once a fault is detected, the fault can be displayed on a diagnostic lamp. The diagnostic code can be read by using Cat ET. A multimeter can be used to check most problems. Also, a multimeter can be used to troubleshoot most problems. The ECM will record most diagnostic codes that are generated during engine operation. These logged codes or intermittent codes can be read by Cat ET.