8206code.fm Page 97 Tuesday, July 7, 1998 11:57 AM
DIAGNOSTIC CODE 3-5 (ADVANCED) Test 2 Checking dynamic timing When performing electrical tests, it is important to wiggle wires and connectors to identify intermittent connection problems.
1. Turn the ignition key to the OFF position. 2. Connect the V-MAC II module connectors.
Blink Code
3-5
PID SID
2
FMI
7
MID
142
Name
Timing Actuator
Failure
Mechanical system not responding
This fault is only active above a specific engine speed and load. It may be inactive by the time the truck reaches the service shop.
Test 1 Checking timing at low idle Follow the instructions in Tests 2 through 72, running the engine at low idle. Proceed to Test 2.
3. Connect a pressure gauge to the diagnostic port. 4. Disconnect the timing valve connector from the wiring harness. 5. Connect a jumper between the two connector halves, using one set of terminals. For example, connect the A terminals (jumper from terminal A on the harness side to terminal A on the sensor side). On the other terminals, use two jumpers to connect the circuit through a digital multimeter set to measure current (AMPS) on the 10A scale. 6. Start the engine. 7. Record the low or high idle timing, the diagnostic port pressure, and the timing valve current. Reconnect the timing valve to the harness when completed.
If the timing status shows the timing is too advanced (diagnostic tool displays “++”), proceed to Test 5. Otherwise, proceed to Test 4.
Test 4 Checking for retarded timing
If the timing status shows the timing is too retarded (diagnostic tool displays “--”), proceed to Test 9. Otherwise, proceed to Test 8.
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