Bonneville V6-3800 3.8L (1991)
Ignition Coil: Description and Operation
Type 1 And Type 2 Coil Identification
Three twin tower ignition coils are combined into a single coil pack unit. This unit is mounted to the ignition module. Each coil provides the spark for
two spark plugs at once simultaneously (waste spark distribution). However, all three coil packs must be replaced as a unit if one of the coils is defective
(Type I coil pack). On Type II coil packs, the coils can be replaced separately. Between the coil pack and the module there are six spade-type terminals.
Three of which are connected together by a common wire from the module, suppling all three coil packs with +12.0 volts. The other three terminals are
individually connected to the module. The module will only connect one coil at a time, in the correct order by suppling and removing the primary circuit
ground to each coil at the proper time.
NOTE: It is important to identify which type (Type I or Type II) of coil pack is used on the vehicle you are working on. Even though they operate in the
same manner, the replacement procedures are different.
