Test Roc - Relay Output Check

Fig 1: Relay Connector Terminals - ACR Relay ID

Fig 2: Relay Connector Terminals - FPR Relay ID

Fig 3: Relay Connector Terminals - HFAN Relay ID

Fig 4: Relay Connector Terminals - LFAN Relay ID

NOTE: Enter this test only when a Code 67 or Code 68 is displayed during self-test procedures (KOEO or KOER) or when directed here from another circuit test or SWITCH MONITOR TEST. This test is intended to diagnose following relays and circuits: A/C Relay (ACR), Fuel Pump Relay (FPR), High Condenser Fan Relay (HCFAN), High Cooling Fan Relay (HFAN), Low Condenser Fan Relay (LCFAN), Low Cooling Fan Relay (LFAN) and Wide Open Throttle A/C Cutoff Relay (WAC).

CIRCUIT PIN IDENTIFICATION

Circuit

Breakout Box Pin No.

PCM Pin

Wire Color

ARC ⁽¹⁾

Green/Black

FPR ⁽²⁾

Light Green

HFAN ⁽³⁾

Blue/Green

LFAN ⁽⁴⁾

Black/Green

⁽¹⁾	When A/C is selected, PCM grounds ACR wire to turn A/C system on.

⁽²⁾	PCM grounds FPR wire to energize fuel pump.

⁽³⁾	PCM grounds HFAN wire to energize the high speed cooling fan.

⁽⁴⁾	PCM grounds LFAN wire to energize the low speed cooling fan.

1) Check System Integrity Visually check all wiring, connectors and components for evidence of damage, shorting or looseness. If fault is found, repair as necessary. If no fault is found, go to next step.

WARNING: Fans will operate when HCFAN, HFAN, LCFAN or LFAN wires are grounded.

2) Perform Relay Click Test Turn ignition off. Install breakout box. Connect PCM to breakout box. Locate relay to be tested. Turn ignition on. Feel and/or listen to relay while grounding appropriate relay test pin at breakout box. If relay clicks, relay is okay. If relay does not click, go to next step.

3) Check For Open Relay Wire To PCM Turn ignition off. With breakout box installed, disconnect PCM connectors. Disconnect relay to be tested. Measure resistance between breakout box test pin of relay being tested and relay terminal to PCM at relay connector. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open wire between PCM and relay connector.

NOTE: When testing HFAN or HCFAN relays, both HFAN and HCFAN relays must be disconnected.

4) Check For Short In Relay Wire To PCM Turn ignition off. With PCM disconnected and breakout box installed, disconnect relay to be tested. Measure resistance between ground and breakout box test pin of relay being tested. If resistance is more than 10,000 ohms, go to next step. If resistance is 10,000 or less, repair short to ground in wire between PCM and relay connector.

5) Check Power To Suspect Relay Turn ignition off. Disconnect relay to be tested. Turn ignition off. Measure voltage at PWR terminal at relay connector. If voltage is more than 10 volts, replace relay. If voltage is 10 volts or less, repair PWR wire.