
Ignition
90-8M0050731 MAY 2011
Page 2A-15
Main Power Relay (MPR)
The main power relay (MPR) is located on the starboard side of the engine. The MPR is controlled by the PCM. After the first
system power up, the MPR is active for approximately five seconds. The PCM will deactivate the MPR unless the crankshaft
position sensor signals the PCM to initiate the MPR. The main power relay supplies 12 volts to the low‑pressure fuel pump,
high‑pressure fuel pump, oil pump, ignition coils, and the fuel injectors.
a -
Main power relay (MPR)
Main Power Relay Test
The main power relay can be tested with the computer diagnostic system (CDS).
Computer Diagnostic System (CDS)
Order through SPX
Adapter Harness
84‑822560A13
Extension Cable
84‑825003A 1
Use the DMT 2004 digital multimeter for all of the following tests.
DMT 2004 Digital Multimeter
91‑892647A01
1. Disconnect the engine harness from the main power relay.
2. Perform a visual inspection of the main power relay spade terminals. Look for loose or corroded spade terminals.
3. Measure the resistance between the main power relay coil terminals 85 (red/purple) and terminal 86 (yellow/purple). Replace
the relay if the resistance is not within the specifications.
30
85
87a
87
86
7602
Meter Test Leads
Meter Scale
Reading (Ω)
Red
Black
Terminal 85
Terminal 86
Auto ohms
85 ± 10 ohms
45196
a
Summary of Contents for 200 OptiMax Jet Drive
Page 5: ...Page iv ...
Page 30: ...General Information Notes 90 8M0050731 MAY 2011 Page 1C 5 ...
Page 43: ...General Information Notes Page 1C 18 90 8M0050731 MAY 2011 ...
Page 84: ...Ignition Notes 90 8M0050731 MAY 2011 Page 2A 3 ...
Page 89: ...Ignition Page 2A 8 90 8M0050731 MAY 2011 Electrical Plate Engine Harness 44731 1 2 3 4 5 6 ...
Page 147: ...Charging and Starting System Notes Page 2B 36 90 8M0050731 MAY 2011 ...
Page 153: ...Timing Synchronizing and Adjusting Notes Page 2C 6 90 8M0050731 MAY 2011 ...
Page 156: ...Fuel Pump Notes 90 8M0050731 MAY 2011 Page 3A 3 ...
Page 245: ...Direct Fuel Injection Notes Page 3B 82 90 8M0050731 MAY 2011 ...
Page 248: ...Oil Injection Notes 90 8M0050731 MAY 2011 Page 3C 3 ...
Page 261: ...Oil Injection Notes Page 3C 16 90 8M0050731 MAY 2011 ...
Page 277: ...Powerhead Page 4A 12 90 8M0050731 MAY 2011 Cylinder Head 14 44903 1 2 3 3 4 5 6 7 8 9 10 ...
Page 326: ...Powerhead 90 8M0050731 MAY 2011 Page 4A 61 Starboard Side Oil Hose Routing 45579 ...
Page 327: ...Powerhead Page 4A 62 90 8M0050731 MAY 2011 Port Side Oil Hose Routing 45580 ...
Page 339: ...Powerhead Notes Page 4A 74 90 8M0050731 MAY 2011 ...
Page 346: ...Cooling Notes 90 8M0050731 MAY 2011 Page 4B 7 ...
Page 349: ...Cooling Notes Page 4B 10 90 8M0050731 MAY 2011 ...