Check For Intermittent Problems

HINT:

A momentary interruption (open circuit) in the connectors and/or wire harness between the sensors and ECUs can be detected by using the ECU data list function of an intelligent tester.

(a) Turn the ignition switch off and connect the intelligent tester to the DLC3.

(b) Turn the ignition switch on.

Harness Signal:

Momentary interruption

1 sec. 1 sec. 1 sec. Intelligent Tester Display:

ERROR I II-LT

(c) Follow the prompts on the intelligent tester to display the DATA LIST and select areas where a momentary interruption should be monitored. HINT:

• A momentary interruption (open circuit) cannot be detected for 3 seconds after the ignition switch is turned on (initial check).

• If the status remains on the ERROR display, check for continuity between the ECU and the sensors, or between ECUs.

• The ERROR display on the intelligent tester remains on for 1 second after the harness signal changes from a momentary interruption (open circuit) to normal condition.

Item (Display)

Measurement Item / Range (Display)

Normal Condition

Diagnostic Note

FR SPD OPN

FR speed sensor open detection / ERROR or NORMAL

ERROR: Momentary interruption NORMAL: Normal

-

FL SPD OPN

FL speed sensor open detection / ERROR or NORMAL

ERROR: Momentary interruption NORMAL: Normal

-

RR SPD OPN

RR speed sensor open detection / ERROR or NORMAL

ERROR: Momentary interruption NORMAL: Normal

-

RL SPD OPN

RL speed sensor open detection / ERROR or NORMAL

ERROR: Momentary interruption NORMAL: Normal

-

F047126

Do It Yourself Car Diagnosis

Do It Yourself Car Diagnosis

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