Note: Never install a jumper wire between the terminal studs of the controller/relay, since immediate damage to all glow plugs may result.
PRIMARY CHECKS
1. Make sure that the engine is at a temperature below 95° F (35° C).
2. Install an ammeter at the controller/relay terminal stud (glow plug side), move the ignition switch to RUN and measure the amperage of each bank of the glow plugs (refer to Figure 20, view A):
• If both banks have a minimum of 55 amperes current flow, the system is working normally.
• If either bank has less than 55 amperes current flow, go to s te p j1.
• If both banks have a zero ampere current flow, go to SECONDARY CHECKS.
3. Install an ammeter in series with one glow plug wire, move the ignition switch to RUN and measure the amperage of the glow plug (refer to Figure 8-20, view B):
• If the glow plug has a current flow of 14 amperes, it is working normally.
• If the glow plug has a current flow of less than 14 amperes, go to step 3.
4. Check the continuity of the glow plug wiring harness from the controller/relay terminal stud to the glow plug terminal (refer to Figure 8-20, view C):
• If the wiring harness has continuity, go to step 4.
• If the wiring harness has no continuity, repair it and check system operation.
5. Replace the glow plug and follow steps 2 and 3 for other glow plugs. Use an AC-type 9G glow plug.
6. When all glow plugs have 14 amperes of current flow, end the diagnosis.
