TM 5-3805-293-23-1
0011
Table 2. Engine Troubleshooting with Codes for the 120M Motor Grader - Continued.
CDI FMI CODE
ERROR/EVENT
CORRECTIVE ACTION
1589-03 Turbocharger Inlet
8. Using a digital multimeter, test for
No Continuity - Rear chassis wiring
Air Pressure Sensor Volt-
continuity between Engine ECM
harness is open, replace rear chassis
age Above Normal Code -
harness connector FA-C17 termi-
wiring harness (WP 0189).
Continued
nal 34 and terminal 55.
Continuity - ECM faulty, replace
There should be good continuity.
Engine ECM (WP 0067).
Resistance should be less than
Connect harness connector FE-C1
5.0 ohms.
(WP 0009, Figure 27) to harness con-
nector FA-C18 (WP 0009, Figure 28).
System Response:
1589-04 Turbocharger Inlet
Air Pressure Sensor Volt-
ECM defaults to an air inlet restriction
age Below Normal Code
of 2.0 psi (14 kPa). Engine derates by
10%.
A warning will appear on display on
instrument panel. ECM will log diag-
nostic code.
Possible Performance Effect:
None.
N OT E
The 5-Volt supply circuit is a common supply circuit which is bussed
internally of the Engine ECM. The supply voltage is 5.0 0.16 Volts.
Output of the 5-Volt supply circuit is at Engine ECM J2-46 circuit T997-
OR, J2-47 circuit L730-OR, J2-48 circuit R997-OR, and J1-42 circuit
R997-OR. The 5-Volt supply circuits are supplied to the intake manifold
pressure sensor terminal 1, the engine oil pressure sensor terminal 1,
and the fuel rail pressure sensor terminal 1.
Each sensor has a return or ground circuit and is a common supply
circuit which is bussed internally of the Engine ECM. The sensor return
circuit is at Engine ECM J2-40 circuit Y940-BR, J2-39 circuit Y947-BR,
J2-38 circuit T993-BR, and J1-34 circuit R993-BR.
The turbocharger air inlet pressure sensor signal circuit is an input to
the Engine ECM at Engine ECM J1-55 circuit F713-OR.
Test Step 1. Test Signal Circuit.
N OT E
Always inspect the harness connectorsthat are involved in the circuit.
Poor connections can often be the cause of a problem in an electrical
circuit. Verify that all connections in the circuit are clean and secure,
and that all connections are in good condition. If a problem with a
connection is found, correct the problem and verify that this diagnostic
code is active before performing this procedure.
Perform open or short circuit test ateach harness connection to identify
correct harness to replace.
Perform this test only if condition is active.
1. Connect MSD (WP 0006). Select
Engine ECM C6.6 120M.
0011-145
Change 1
