831255A 6 Mercury PISTON RING SET

Table 1
Diagnostic Codes Table
Code and Description Conditions which Generate this Code System Response
827-8 Left Exhaust Temperature Sensor : Abnormal Frequency, Pulse Width, or Period The Electronic Control Module (ECM) detects a sensor frequency that is greater than 1000 Hz or less than 150 Hz.
The ECM detects a duty cycle that is greater than 90 percent or a duty cycle that is less than 10 percent. The value of the parameter is set to zero.
The code is logged.
828-8 Right Exhaust Temperature Sensor : Abnormal Frequency, Pulse Width, or Period The ECM detects a sensor frequency that is greater than 1000 Hz or less than 150 Hz.
The ECM detects a duty cycle that is greater than 90 percent or a duty cycle that is less than 10 percent. System OperationUse this procedure to troubleshoot any suspect problems with the following sensors:
Left exhaust temperature sensor
Right exhaust temperature sensorThe "Pulse Width Modulated (PWM)" sensors provide a signal to the engine's ECM for certain engine operating conditions. The sensors receive a 8.0 0.4 VDC regulated voltage from the ECM.The sensor's wires are routed from the ECM to the sensor connectors. The following list gives the terminal locations for the sensor connector.
Terminal A 8 V supply
Terminal B sensor return
Terminal C sensor signalThe ECM performs an automatic calibration of these sensors whenever the ECM is powered and the engine has been off for at least five seconds.The ECM provides short circuit protection for the internal power supply. A short circuit to the battery will not damage the internal power supply.
Illustration 1 g01340318
Typical schematic
Illustration 2 g01213937
P1 ECM connector
(P1-4) "8 V digital sensor supply (LH)"
(P1-5) "Digital sensor return (LH)"
(P1-11) Left exhaust temperature
(P1-12) Right exhaust temperature
Illustration 3 g01327661
P2 ECM connector
(P2-56) "8 V digital sensor supply (RH)"
(P2-66) "Digital sensor return (RH)"
Illustration 4 g01327759
Terminal locations for the A-C1/E-C2 RH rigid harness connectors and the C-C1/E-C1 LH rigid harness connectors
(Terminal C) "8 V digital sensor supply (RH)"
(Terminal D) "Digital sensor return (RH)"
(Terminal R) "Right exhaust temperature"
Illustration 5 g01337991
Connector locations
(1) A-C1/E-C2 RH rigid harness connectors
(2) A-C2/J-C2 RH rigid harness connectors
(3) P-C1/A-C90 Connectors for the power distribution panel
(4) P-C2/A-C91 Connectors for the power distribution panel
(5) G-C6/F-C2/F-C1/A-C92 Connectors for a RH Control panel
(6) C-C22 Connection for the P2 ECM connector
(7) C-C15 Connection for the P1 ECM connector
(8) G-C6/F-C2/F-C1/C-C17 Connectors for a LH Control panel
(9) C-C18/TB-C1 Customer connectors
(10) C-C2/J-C1 LH rigid harness connectors
(11) C-C1/E-C1 LH rigid harness connectors
Illustration 6 g01234146
Location of ECM connectors
Illustration 7 g01243506
Sensor connector
(Pin A) Sensor supply
(Pin B) Sensor return
(Pin C) Signal Test Step 1. Check for an "Active" Diagnostic Code
Turn the ECS to the OFF/RESET position.
Connect Caterpillar Electronic Technician (ET) to the service tool connector.
Turn the ECS to the STOP position.
Monitor the diagnostic codes on Cat ET. Check and record any diagnostic codes. Note: Wait at least 30 seconds in order for the diagnostic codes to become active.
Determine if a diagnostic code has occurred several times. Note: A diagnostic code that is logged several times is an indication of an intermittent problem. Most intermittent problems are the result of a bad connection between a socket and a pin in a connector or a bad connection between a wire and a terminal.
Determine if a 8 diagnostic code is active for one of the exhaust temperature sensors: Expected Result:No diagnostic code is active for the exhaust temperature sensors.Results:
OK - No diagnostic codes are active.Repair: If the problem is intermittent, refer to Troubleshooting, "Electrical Connectors - Inspect" for the correct procedures for inspecting electrical connectors.STOP
Not OK - A 8 diagnostic code is active or the diagnostic code is logged several times. Proceed to Test Step 2.Test Step 2. Check the Digital Supply Voltage at the Sensor Connector
Disconnect the suspect sensor(s) at the sensor connector:
Measure the voltage on the ECM side of the sensor connector between pin A and pin B for the suspect sensor(s). Expected Result:The supply voltage is 8.0 0.4 VDC.Results:
OK - The supply voltage is 8.0 0.4 VDC. Proceed to Test Step 3.
Not OK - The supply voltage is not 8.0 0.4 VDC.Repair: Refer to Troubleshooting, "Sensor Supply - Test".STOPTest Step 3. Check the Digital Sensor's Signal Frequency and the Duty Cycle at the Sensor Connector
Turn the ECS to the OFF/RESET position.
Remove the sensor's signal wire from pin C of the sensor connector.
Reconnect the sensor.
Turn the ECS to the STOP position.
Measure the frequency and the duty cycle between the sensor's signal wire and pin B of the suspect digital sensor at the sensor connector.
Turn the ECS to the OFF/RESET position.
Replace