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Testing Procedure

CAUTION: Tests requiring connector to be removed from Engine Control Module (ECM), must have meter probes inserted into back of connector. If probes are inserted into connector sockets, damage will occur to sockets resulting in poor connections when connector is reconnected.

To carry out tests when 40 pin connector is connected to the ECM, it is necessary to remove the two screws securing the shroud to the connector to enable the multi-meter probes to be inserted into the back of the appropriate pin. See Figure . For pin number identification, pin numbers 1, 13, 14, 27, 28 and 40 are molded onto rear of connector. See Figure . To gain access to ECM remove front seat base trim of front right seat.

  1. Before proceeding with testing vehicle, perform preliminary checks. See PRELIMINARY CHECKS  . If no problem is present, go to next step.
  2. If Lucas Diagnostic Equipment or Test Book cannot communicate with the ECM and engine cranks but does not start, go to next step. If scan tool other then Lucas Diagnostic Equipment or Test Book cannot communicate with ECM and engine cranks but does not start, see scan tool manufacturers procedure for checking scan tool performance. If no problem is present, check tune select resistor. See CODE 21: TUNE SELECT RESISTOR  . If tune select resistor is okay, check engine control module power and ground circuits, see ENGINE CONTROL MODULE under COMPUTERIZED ENGINE CONTROLS in SYSTEM & COMPONENT TESTING - RANGE ROVER article.
  3. Check Lucas Diagnostic Equipment or Test Book connections. If connections are okay, go to next step.
  4. On Lucas Diagnostic Equipment check that the memory card is correct and inserted properly. On Test Book check that CD is correct and inserted properly. Check Lucas Diagnostic Equipment or Test Book internal power source. If no problem is present, check tune select resistor. See CODE 21: TUNE SELECT RESISTOR  . If tune select resistor is okay, check engine control module power and ground circuits, see ENGINE CONTROL MODULE under COMPUTERIZED ENGINE CONTROLS in SYSTEM & COMPONENT TESTING - RANGE ROVER article.
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