OXS Frequency Valve
- Disconnect harness connector from OXS frequency valve. Using a LED Test Light (US 1115), connect Red lead to terminal No. one and Black lead to terminal No. 2.
- Perform output code self-diagnosis as previously described. When code appears, LED test light must be off. If light is off, replace OXS frequency valve.
- If light came on, ensure 12 volts are present between oxygen sensor terminal No. 1 and ground. If necessary, repair wiring or circuits.
- If 12 volts are present, turn ignition off. Disconnect ECU harness connector. Check for about 10 ohms in wire between ECU terminal No. 8 and oxygen sensor terminal No. 2. See Figure . If ohms are not as specified, check for an open circuit in wire. If circuit is not open, replace ECU.