Diagnostic Aids

Circuits are identified in all capital letters (acronyms). For example, Profile Ignition Pickup is identified as PIP. Manufacturer's breakout box overlay test terminals are identified by a "J" prefix. For example, J31 (PIP). The J31 indicates that the measurement is to be taken at terminal No. 31 at the breakout box. The (PIP) indicates that the Profile Ignition Pickup circuit is being checked.

When the letter "I" follows the circuit identification, it implies that the measurement is being taken at the ICM. For example, J31 (PIP I). The (PIP I) implies that the measurement is of the PIP circuit at the ICM.

When the letter "S" follows the circuit identification, it implies that the measurement is being taken at the CKP sensor. For example, J32 (CKP+ S). The (CKP+ S) implies that the measurement is of the CKP sensor positive circuit at the CKP sensor. When the letter "C" follows the circuit identification, it implies that the measurement is being taken at the coil. For example, J10 (LC3C). The (LC3C) implies that the measurement is of the C3 circuit at the left coil pack.

The following information should also be noted during testing:

When checking a wiring harness, perform both a visual inspection and a continuity test. Inspect terminal connector pins for damage, bending, spreading and corrosion when directed to remove a connector.
Spark timing adjustments are not possible. Timing is controlled by ICM with input from PCM.
When checking voltage drop to GROUND, circuit must have a voltage drop of less than one volt.
Battery voltage (VBAT) is any voltage reading within 2 volts of actual battery voltage.
EEC-IV Breakout Box (T83L-50-EEC-IV) connected to EI diagnostic cable is referred to as breakout box or EI breakout box. If a second breakout box is connected to PCM wiring harness connector, it will be referred to as second or PCM breakout box. This setup allows testing of EI components and wiring harness circuits.

NOTE: A 12-volt incandescent (high voltage) test light should not be used to test circuit signals. It will load circuit and may cause incorrect measurements or faulty EI/PCM operation (engine stall).

4.6L EI PINPOINT TEST INDEX

Result

Pinpoint Test & Step

No Start

No Codes

PASS Code 111

Code 226

Code 211 (PIP Signal At PCM Fault)

Malfunction Indicator Light (MIL) On During Cranking

Engine Runs

Code 212 Or 226 (IDM Signal Fault At PCM)

Code 213 (SPOUT Circuit Fault)

Code 215 And/Or 216 (Coil 1 Or Coil 2 Fault)

D19

Code 217 And/Or 238 (Coil 3 Or Coil 4 Fault)

Lack Of Power Or Poor Fuel Economy

Engine Miss

⁽¹⁾ **

Engine Intermittent Driveability Complaint

⁽²⁾ **

⁽¹⁾	See PINPOINT TEST F under ELECTRONIC IGNITION (EI) LOW DATA RATE SYSTEM 3.0L SHO, 3.2L & 3.8L SC).

⁽²⁾	See PINPOINT TEST G under ELECTRONIC IGNITION (EI) LOW DATA RATE SYSTEM 3.0L SHO, 3.2L & 3.8L SC).

WARNING: DO NOT connect PCM to EI diagnostic cable; 60-pin connector on this harness may be connected to a breakout box only. If PCM is connected to EI diagnostic cable, PCM may be damaged. Some tests may require a second breakout box to be connected to PCM 60-pin connector. When a second breakout box is used, PCM should be disconnected at all times. Never connect PCM to breakout box when performing EI diagnostics.

Fig 1: EI Diagnostic Cable Diagram (4.6L)

Fig 2: EI Wiring Diagram (4.6L)

Fig 3: EI System Pin Voltage Chart (4.6L)

Fig 4: EI Signal Diagram (4.6L)

Fig 5: EI Block Diagram (4.6L)