Block Water Pressure Sensor Tests - Mercury V6 175 Diagnostic Manual

The block water pressure sensor, if equipped, is located on the top aft of the engine, near the exhaust manifold.
a

Block Water Pressure Sensor Tests

Monitor the pressure (data item SeaPumpPress) on the CDS G3 Live Data screen. If the block water pressure sensor does
not appear to indicate a pressure change when engine RPM is varied, shake or move the sensor harness and connector. If the
pressure begins to change, look for a broken, loose, or corroded wire.
CDS G3 Interface Kit
Continue testing with the engine OFF:
1. Disconnect the engine harness connector from the sensor.
2. Visually inspect the sensor pins and the wires coming from the engine harness connector. Look for broken, bent, or
corroded pins at the sensor and loose, broken, or corroded wires at the engine harness connector.
3. Measure the resistance between pins A, B, and C of the block water pressure sensor.
DMT 2004 Digital Multimeter
Meter Test Leads
Red
Pin A
Pin A
Pin B
4. Perform a continuity check of the sensor wiring in the engine harness, between the sensor connector and the PCM. Note
that there are splices in both the power and ground circuits.
NOTE: Sensor power splice numbers vary between DTS and mechanical models.
DMT 2004 Digital Multimeter
90-8M0146617 eng JULY 2018
a
b
c
67546
Black
Pin B
Pin C
Pin C
b
67492
a - Pin A – ground (–)
b - Pin B – power (+)
c - Pin C – pressure signal
Meter Scale
Auto
Auto
Auto
© 2018 Mercury Marine
a - Exhaust manifold
b - Block water pressure sensor
8M0138392
91‑892647A01
Reading
At 21 °C (70 °F)
78.4–145.6 kΩ
182.0–338.0 kΩ
100.8–187.2 kΩ
91‑892647A01
Sensors
Page 5A-11