Monitor Description
OUTLINE OF DIAGNOSIS
Detect malfunction of soaking timer IC by the five diagnoses below.
Judge as NG when malfunction is detected 2 times or more consecutively in any diagnosis of Monitor #1 - 5.
| Monitor Number | Explanation | Time required for diagnosis |
|---|---|---|
| Monitor #1 <Timer diagnosis> |
Perform diagnosis of the soaking timer IC accuracy | 128 ms |
| Monitor #2 <Full count diagnosis> |
Perform diagnosis of the soaking timer IC counter function | 128 ms |
| Monitor #3 <Soaking timer IC setting diagnosis> |
Perform diagnosis of communication between ECM and soaking timer IC | 128 ms |
| Monitor #4 <Timer diagnosis (during soaking)> |
Perform diagnosis of the soaking timer IC accuracy during soaking | None |
| Monitor #5 <Wake-up diagnosis> |
Perform diagnosis of wake-up function | None |
COMPONENT DESCRIPTION
The soak timer IC is built into the ECM.
EXECUTION CONDITION
| Secondary parameters | Execution condition |
|---|---|
| Ignition switch | OFF |
| Battery voltage | 10.9 V or higher |
| Elapsed time after starting the engine | More than 19 s and Less than 61439 s |
| Secondary parameters | Execution condition |
|---|---|
| Ignition switch | OFF |
| Battery voltage | 10.9 V or higher |
| Counter in ECM | 4 s or more |
| Secondary parameters | Execution condition |
|---|---|
| Ignition switch | OFF |
| Battery voltage | 10.9 V or higher |
| Secondary parameters | Execution condition |
|---|---|
| Ignition switch | OFF |
| Battery voltage | 10.9 V or higher |
| Secondary parameters | Execution condition |
|---|---|
| Ignition switch | OFF |
| Time in the soaking timer IC | More than 3600s |
GENERAL DRIVING CYCLE
Perform the diagnosis only once when the ignition switch is OFF and when the ignition switch is ON after the soaking of one hour or more.
DIAGNOSTIC METHOD
Monitor#1 <Timer diagnosis>
Start the count up operation of counters in ECM and in soaking timer IC when the engine is started.
Judge as timer malfunction if the difference between the counter in ECM and counter in soaking timer IC exceeds the allowable limit when the ignition switch is OFF.
Judge as NG when the following conditions are established.
Judgment value
| Malfunction Criteria | Threshold Value |
|---|---|
| Counter in ECM - Counter in soaking timer IC / Counter in ECM | Less than -0.24, or more than 0.24 |
Monitor#2 <Full count diagnosis>
Reset the counter in soaking timer IC and start the count up operation.
Judge as full count diagnosis malfunction if counter in soaking timer IC is not the specified value after 4 seconds.
Judge as NG when the following conditions are established.
Judgment value
| Malfunction Criteria | Threshold Value |
|---|---|
| Counter in soaking timer IC | Not equal to 65535 counts |
Monitor#3 <Soaking timer IC setting diagnosis>
When setting the activation setting time to soaking timer IC, compare the writing value to soaking timer IC with read out value. Judge as malfunction if the values do not match 3 times in a row.
Judge as NG when the following conditions are established.
Judgment value
| Malfunction Criteria | Threshold Value |
|---|---|
| Writing value and read out value when setting the soaking timer | Unmatch |
Monitor#4 <Timer diagnosis (during soaking)>
Wake-up at the predetermined interval until 5, 7 or 9.5 hours have passed after the ignition switch is OFF, and compare the counter in soaking timer IC with the counter in ECM.
Judge as malfunction if the counter in soaking timer IC is counted up to maximum value when the counter in ECM is 1636 ms, or if the counter in soaking timer IC is not counted up to maximum value when the counter in ECM is 2456 ms.
Judge as NG when the following conditions are established.
Judgment value
| Malfunction Criteria | Threshold Value |
|---|---|
| Counter in ECM | 1636 ms or less |
| Counter in soaking timer IC | 65535 counts |
| Or, | |
| Counter in ECM | 2456 ms or more |
| Counter in soaking timer IC | Not equal to 65535 counts |
Monitor#5 <Wake-up diagnosis>
Store the number of wake-up activation when the ECM wakes up by the soaking timer IC.
Next time when the ignition switch is ON, if the number of wake-up activation does not reach the predetermined value even though the counter in soaking timer IC operates 1 hour or more, judge as wake-up malfunction.
Judge as NG when the following conditions are established.
Judgment value
| Malfunction Criteria | Threshold Value |
|---|---|
| Number of wake-up | Not equal to wake-up indication count |
Time needed for diagnosis
Monitor#1: 0.128 s
Monitor#2: 0.128 s
Monitor#3: 0.128 s
Monitor#4: Less than 1 s
Monitor#5: Less than 1 s
Malfunction indicator light illumination
Illuminates when malfunction occurs in 2 continuous driving cycles.