DDEC TROUBLESHOOTING
86.3 TROUBLESHOOTING FLASH CODE 86
The following procedure will troubleshoot Flash Code 86.
86.3.1
Multiple Code Check
Perform the following steps to check for multiple codes.
1. Turn ignition ON.
2. Plug in DDR.
3. Read active codes.
[a] If active code 73/3 was logged, and no other codes were logged, refer to section 86.3.2.
[b] If active code 73/4 and any other codes were logged, refer to section 86.3.3.
[c] If any codes other than 73/3 were logged, refer to section 91.1.
86.3.2
Sensor Check
Perform the following steps to check the sensor.
1. Turn ignition OFF.
2. Disconnect the Pressure Governor System (PGS) sensor connector.
3. Turn ignition ON.
4. Start engine and operate the PGS in the PRESSURE mode.
5. Read active codes.
[a] If active code 73/3 and any other codes were logged, refer to section 86.3.5.
[b] If active code 73/4 and any other codes except 73/3 were logged,
refer to section 86.3.3.
86.3.3
Return Circuit Check
Perform the following steps to check the return circuit.
1. Turn vehicle ignition OFF.
2. Disconnect the vehicle harness connector at the ECM. See Figure 86-2.
3. Install a jumper wire between pins A and B of the PGS sensor harness connector.
4. Measure resistance between sockets D3 and C3 on the vehicle harness connectors.
[a] If the resistance measurement is less than or equal to 5 , refer to section 86.3.4.
All information subject to change without notice.
6SE497 9709 Copyright © 1997 DETROIT DIESEL CORPORATION
86-5
