D18 - Key Power Check
NOTE:
Perform this test ONLY when a Code 55 is displayed in QUICK TEST.
To prevent replacement of good components, be aware that the following non-EEC related areas may be at fault: charging system overcharging, battery charger connected with engine running or jump starting vehicle.
- Code 55: Checking Continuity of Key Power Circuit. Code 55 indicates key power circuit voltage is low. Possible causes for this fault are: circuit shorted to ground or faulty ECA. Turn key off and wait 10 seconds. Install breakout box and connect ECA. Disconnect the EEC-IV power relay or IRCM. Set DVOM on 200-ohm scale. Measure the following resistances: If resistance is less than 5 ohms, go to next step. If resistance is greater than 5 ohms, repair open circuit, reconnect system components and rerun QUICK TEST.
- Checking KEY POWER (KPWR) Circuit For Shorts to Ground. Turn key off, disconnect ECA and install breakout box. Disconnect power relay or IRCM. Set DVOM on 200K-ohm scale and measure resistance between test pin No. 5 and test pins No. 40, 46, and 60, at the breakout box. If resistance is greater than 10K ohms, replace ECA, reconnect components and retest system. If resistance is less than 10K ohms, repair short circuit and rerun QUICK TEST.