GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 1997 🢒 GMC P62 Commercial Chassis 🢒 Engine 🢒 Engine Electrical 🢒 Starter Solenoid Clicks, Engine Does Not Crank

Circuit Description

The generator provides voltage to operate the vehicle's electrical system and to charge its battery. A magnetic field is created when the current flows through the rotor. This field rotates as the rotor is driven by the engine, creating an AC voltage in the stator windings. The AC voltage is converted to DC by the rectifier bridge and is supplied to the electrical system at the battery terminal.

The generator's regulator uses digital techniques in order to supply the rotor current and thereby control the output voltage. The rotor current is proportional to the width of the electrical pulses supplied to it by the regulator. When the ignition switch is placed in RUN, narrow width pulses are supplied to the rotor, creating a weak magnetic field. When the engine is started, the regulator senses generator rotation by detecting AC voltage at the stator through an internal wire. Once the engine is running, the regulator varies the field current by controlling the pulse width. This regulates the generator output voltage for proper battery charging and electrical system operation.

The digital regulator controls the VOLTS indicator lamp with a solid-state lamp driver. The lamp driver turns on the lamp whenever undervoltage, overvoltage or a stopped generator is detected.

Starter Solenoid Clicks, Engine Does Not Crank

Step

Action

Value(s)

Yes

No

1
  1. The engine and the batteries must be at normal operating temperatures.
  2. No other engine defects exist which might cause cranking problems.
  3. Check the condition of the battery cable and the terminal connections and repair if necessary.
  4. Test the battery and replace it if necessary. Refer to Battery Load Testing.
  5. Check the charging system.
  6. Check for continuous battery drain. Refer to Battery Electrical Drain/Parasitic Load

Are the symptoms still present?

--

Go to Step 2

System OK

2
  1. Disable the ignition in order to prevent the engine from starting unexpectedly during testing.
  2. Connect a voltmeter between the engine block and the battery negative terminal (voltmeter positive lead on the engine block).
  3. Turn the key to START.
  4. Observe the voltage.

Does the voltmeter indicate more than the specified value?

0.5V

Go to Step 3

Go to Step 4

3
  1. Clean and tighten the ground cable connection.
  2. Replace the cable if repairing the connection does not eliminate the excessive voltage drop.

Is the repair complete?

--

System OK

--

4
  1. Connect a voltmeter to the starter B terminal.
  2. Observe the voltmeter while the engine is cranking.

Is the voltage more than the specified value?

9V

Go to Step 5

Go to Step 6

5

Repair the starter.

Is the repair complete?

B+

System OK

--

6
  1. Clean and tighten the positive battery cable connection.
  2. Replace the positive battery cable if repairing the connection does not solve the problem.

Does repairing the positive cable solve the problem?

--

System OK

Go to Step 7

7

Replace the starter.

Is the repair complete?

--

System OK

--