Diagnostic Aids

WARNING: This page does not describe the selected car, but rather 32 other vehicles, including the 2003 Mercury Sable, 2003 Mercury Mountaineer, 2003 Mercury Marauder, 2003 Mercury Grand Marquis, and 2003 Lincoln Town Car. However, it is still accessible from the selected car via links, so may be relevant.

Perform this test when instructed during QUICK TEST or if directed by other test procedures. This test is used to diagnose the following:

Ignition Coil Pack(s)
Ignition Coil Wiring Harness
IGN START/RUN Circuit To Coil Pack(s)
Powertrain Control Module (PCM)

NOTE: Electronic ignition engine timing is entirely controlled by PCM. Electronic ignition timing is not adjustable. DO NOT attempt to check base timing. You will receive false readings.

Fig 1: Identifying 4-Tower Coil Pack Wiring Harness Connector Terminals (Escape 2.0L, Focus, Ranger 2.3L & ZX2)

Courtesy of FORD MOTOR CO.

Fig 2: Identifying Horizontal 6-Tower Coil Pack Wiring Harness Connector Terminals (Explorer Sport & Explorer Sport Trac, Explorer & Mountaineer 4.0L SOHC With 104-Pin PCM, & Ranger 4.0L)

Courtesy of FORD MOTOR CO.

Fig 3: Identifying Horizontal 6-Tower Coil Pack Wiring Harness Connector Terminals (Explorer & Mountaineer 4.0L SOHC With 150-Pin PCM)

Courtesy of FORD MOTOR CO.

Fig 4: Identifying Series 5 Coil Pack Wiring Harness Connector Terminals (Econoline 4.2L, Mustang 3.8L, Pickup 4.2L, Ranger 3.0L, Sable & Taurus 3.0L 2V, & Windstar)

Courtesy of FORD MOTOR CO.

NOTE: Performing step 1) and comparing test results to IGNITION COIL-TO-CYLINDER CORRELATION (COIL PACK) table can help determine which coil is not firing.

IGNITION COIL-TO-CYLINDER CORRELATION (COIL PACK)

Application & Cylinder No.	Coil Driver	PCM Terminal No.	DTC
4-Cylinder
1	A	26	P0351
3	B	52	P0352
4	A	26	P0351
2	B	52	P0352
V6 (104-Pin PCM 4.0L SOHC)
1	A	26	P0351
4	B	52	P0352
2	C	78	P0353
5	A	26	P0351
3	B	52	P0352
6	C	78	P0353
V6 (150-Pin PCM 4.0L SOHC)
1	A	E31	P0351
4	B	E23	P0352
2	C	E13	P0353
5	A	E31	P0351
3	B	E23	P0352
6	C	E13	P0353