This diagnosis is typically oil pressure very low. Perform the following steps to troubleshoot an
oil pressure very low fault
26.4.1
Multiple Codes Check
Check for multiple codes as follows:
1. Check for additional active fault codes.
[a] If fault code 100/3 is active in addition to code 100/4, refer to section 26.2.1.
[b] If fault code 100/4 is active in addition to code 100/4, refer to section 26.3.1.
[c] If only fault code 100/18 is active, go to step 2.
2. Start engine and check oil pressure.
[a] If pressure is fluctuating, go to step 3.
[b] If pressure is low but stable, go to step 4.
3. Stop the engine and allow sufficient time for the oil to drain into the oil pan. Perform
the following steps:
[a] Check the oil level. Add recommended oil to bring it to the proper level, if required.
[b] Check for faulty oil gage. Replace, if required.
[c] Check for loose or cracked oil pump suction pipe. Repair or replace, as required.
[d] Check for loose drive or driven oil pump gear. Repair or replace, as required.
[e] Check for faulty oil pressure relief valve. Repair or replace, as required.
[f] Refer to section 26.4.1.1.
4. Stop the engine and allow sufficient time for the oil to drain into the oil pan. Check the
oil level.
[a] If oil is above maximum level with no oil previously added, go to step 5.
[b] If oil is not above maximum level, contact Detroit Diesel Customer Support Center
(313–592–5800).
5. Check for possible fuel in oil.
[a] If fuel is found, locate and repair source of fuel leak. Change the Oil. Refer to section
26.4.1.1.
[b] If fuel is not found, contact Detroit Diesel Customer Support Center at 313–592–5800.
26.4.1.1
Verify Repairs
Verify repairs as follows:
1. Turn ignition OFF.
2. Reconnect any electrical connections that were disconnected to perform the diagnosis.
3. Clear codes with DDDL 7.0 or latest version.
4. Start and bring engine up to operating temperature (over 140°F/60°C).
5. Verify operation is satisfactory and no warning lamps illuminate. If warning lamps
illuminate, troubleshoot the codes. If assistance is required, call the Detroit Diesel
Customer Support Center at 313–592–5800.
