Test Aa: No Start - Gasoline Mode: Testing

WARNING: This page is about a different car, the 2002 Ford Pickup and 2002 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.

CAUTION: Always disconnect bi-fuel relay module power supply 3-pin harness connector C495 before disconnecting or reconnecting compuvalve main harness connector C1294 to avoid damaging compuvalve or connectors. See Figure.

1) By-Pass Fuel Pump Intercept Circuits
Turn ignition off. Disconnect fuel pump intercept harness connectors C463 and C4131. See Figure and Figure . Connector C463 and C4131 are located in center of vehicle, near fuel tank. Move fuel pump intercept harness aside and reconnect base vehicle fuel pump harness connectors. Place ALT fuel switch in GAS position. Attempt to start engine. If engine starts with ALT fuel switch in GAS position, go to next step. If engine does not start with ALT fuel switch in GAS position, repair base vehicle gasoline fuel concern. See NO-START/NORMAL CRANK under SYMPTOMS in TROUBLE SHOOTING - NO CODES - EEC-V - GASOLINE & NGV article.

NOTE: During bi-fuel relay module, fuse, and relay diagnostics, intermittent failures are possible. During each continuity test a wiggle test should also be performed, including tapping relays during testing.

2) Check Bi-Fuel Relay Operation
Turn ignition off. Disconnect bi-fuel relay module power supply harness connector C495. See Figure. Also, disconnect bi-fuel relay module harness connectors C410 and C4001. Using DVOM, measure resistance between bi-fuel relay module harness connector C4001F terminals No. 1 and 2. See Figure and Figure . If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, replace bi-fuel relay module.

3) Check Fuel Pump Intercept Harness

Ensure ignition is off. Reconnect fuel pump intercept harness connectors C463 and C4131. Connect a jumper wire between bi-fuel relay module harness connector C4001M terminals No. 1 and 2. Ensure ALT fuel switch is in GAS position. Attempt to start engine. If engine starts with ALT fuel switch in GAS position, go to next step. If engine does not start with ALT fuel switch in GAS position, repair or replace fuel pump intercept harness (Pink/Black wire) between bi-fuel relay module and fuel tank unit. See WIRING DIAGRAMS article.

4) Check Bi-fuel Relay Module

Ensure ignition is off. Reconnect bi-fuel relay module connector C410 and bi-fuel relay module power supply connector C495. Ensure ALT fuel switch is in GAS position. Turn ignition on. Using DVOM, measure resistance between bi-fuel relay module connector C4001F terminals No. 1 and 2. If resistance is 5 ohms or more, go to next step. If resistance is less than 5 ohms, reconnect all connectors and restart engine. If no-start fault still exists, go to next step.

5) Check Main Harness

Turn ignition off. Ensure bi-fuel relay module harness connector C4001 is disconnected. Ensure ALT fuel switch is in GAS position. Using DVOM, measure and record resistance between bi-fuel relay module connector C4001F terminals No. 1 and 2. Turn ignition on. Using DVOM, again measure resistance between bi-fuel relay module connector C4001F terminals No. 1 and 2. If resistance less than 5 ohms with ignition off and more than 10 k/ohms with ignition on, go to next step. If resistance 5 ohms or more with ignition off and 10 k/ohms or less with ignition on, reconnect bi-fuel relay module connector C4001. If no-start fault still exists, replace bi-fuel relay module.

6) Check Compuvalve

Turn ignition off. Ensure ALT fuel switch is in GAS position. Disconnect bi-fuel relay module power supply connector C495. Disconnect compuvalve 64-pin harness connector C1294. Compuvalve is located in right side, rear of engine compartment. Reconnect bi-fuel relay module power supply connector C495. Using DVOM, measure resistance between chassis ground and compuvalve harness connector C1294F terminal No. 5. See Figure. If resistance is more than 10 k/ohms, perform COMPUVALVE CHECK under QUICK TEST. If no-start fault still exists, replace compuvalve. If resistance is 10 k/ohms or less, repair short to ground in White wire between compuvalve harness connector C1294F terminal No. 5 and bi-fuel relay module harness connector C410M terminal "B". See WIRING DIAGRAMS article.