on the application, these slots are spaced around the ring in a specific configuration. As
the ring rotates, the slots pass between the hall-effect switch, and alternately turns the
voltage off and on. When a slot aligns with the hall-effect switch, the controller sees
voltage on the signal line. When the area between slots passes the hall-effect switch, the
signal is pulled low. This results in a voltage of 0V
–0.1V at the controller.
The rotation of the interrupter ring causes the signal to toggle, which causes a continual
series of digital pulses on the signal line. This digital pulse is the timing signal that is used
by the ignition module or engine computer to open and close the primary circuit. The
controller processes these pulses as the RPM signal.
Ignition Coil
The heart of the automotive ignition system is the ignition coil. The ignition coil is a step-up
transformer, since it boosts battery voltage to the high voltage that is necessary for proper
combustion.
The ignition coil consists of a primary winding and secondary winding wrapped around a
soft iron core. The primary winding is made up of several hundred turns of heavy wire,
while the secondary winding consists of thousands of turns of fine wire. The iron core is
used to conduct magnetic lines of force efficiently.
When current flows through the primary winding, a magnetic field is created. The more
time current is permitted to flow, the stronger the magnetic field becomes. When the
current is turned off, the magnetic field collapses causing a high voltage to be induced in
the secondary winding through the process of induction.
A few hundred volts will be generated in the primary winding because of the collapsing
magnetic field across the heavy primary wire. However, as the magnetic lines of force cut
across the thousands of turns of fine wire in the secondary, a far greater voltage is
produced. The production of primary voltage is called self-induction, since the primary
winding essentially magnifies its own initial voltage when the magnetic field collapses.
Related Symptoms
Faulty ignition system components along with loose connections, bad grounds, high
resistance or opens in the circuit, may cause the following symptoms:
No start condition
Stalling after cold start
Stalling after hot start
Surging off idle
Extended crank time when engine is cold
Unstable idle
Running rough during off idle acceleration
Bucking
Hesitation
Stumble
Poor fuel economy
Spark knock
Summary of Contents for TrailBlazer
Page 1: ......
Page 26: ...Fig 3 Typical body and undervehicle maintenance locations Refer to chart for descriptions ...
Page 29: ......
Page 30: ......
Page 31: ......
Page 175: ...Spring free length check Valve spring squareness check ...
Page 192: ...Front of piston mark ...
Page 361: ...5 3L Engine Except Saab Underhood Fuse Block 2003 2005 Early Production ...
Page 469: ...Removing the outer band from the CV boot Removing the inner band from the CV boot ...
Page 470: ...Removing the CV boot from the joint housing Clean the CV joint housing prior to removing boot ...
Page 471: ...Removing the CV joint housing assembly Removing the CV joint ...
Page 472: ...Inspecting the CV joint housing Removing the CV joint outer snap ring ...
Page 473: ...Checking the CV joint snap ring for wear CV joint snap ring typical ...
Page 474: ...Removing the CV joint assembly Removing the CV joint inner snap ring ...
Page 475: ...Installing the CV joint assembly typical ...
Page 553: ...9 Torque the lug nuts to specification 10 Lower the vehicle ...
Page 556: ...Toe in Frame Misalignment Frame misalignment ...
Page 588: ...Bleeding caliper ...
Page 624: ...Manifold gauge set components Refrigerant recovery recycling station ...
Page 676: ...A C Specifications ...
Page 677: ......