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Cold Start Injector Circuit

  1. Turn ignition off. Pull back the right front floor mat. Remove ECM protective cover. Connect Check Harness (09990-01000) to ECM harness, but NOT to ECM. See USING CHECK HARNESS  under INTRODUCTION. Disconnect electrical connector from cold start injector time switch. See COMPONENT LOCATIONS  under INTRODUCTION. Turn ignition on.
  2. While cranking engine, measure voltage between chassis ground and terminal No. 78 (Black/Red wire) of ECM connector "B". To identify ECM connectors and terminals, see Figure. If battery voltage is measured, go to step 4).
  3. If battery voltage is not measured, measure resistance of cold start injector. See COLD START INJECTOR RESISTANCE under COLD START INJECTOR SYSTEM . If resistance is as specified, repair circuit between ECM and cold start injector, or between cold start injector and battery.
  4. Measure resistance of cold start injector time switch. See COLD START INJECTOR TIME SWITCH RESISTANCE under COLD START INJECTOR SYSTEM . If resistance is as specified, check circuit between cold start injector and cold start injector time switch. If circuit is okay, check cold start injector spray pattern. See COLD START INJECTOR SPRAY PATTERN under COLD START INJECTOR SYSTEM . If spray pattern is okay, cold start injector circuit is okay.
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