|
|
CRUISE CONTROL ENGINE AND EMISSION CONTROL 17-9 OPERATION This circuit judges the signals of each switch (cruise − and RES +) of the cruise control switch. The engine-ECU detects the • When all switches are released: 4.7 − 5.0 volts • When the cruise control ON/OFF switch is pressed: 0.9 − 1.7 volt • When the CANCEL switch is pressed: 1.9 − 2.7 volts • When the SET − switch is pressed: 2.9 − 3.6 volts • When the RES + switch is pressed: 3.8 − 4.5 volts DIAGNOSIS CODE SET CONDITIONS • If the cruise control switch is operated, this diag- nosis code will be set when the engine-ECU ter- • Or, this code is set when the SET − switch or RES + switch is stuck to ON. PROBABLE CAUSES • Damaged harness or connector. • Malfunction of the cruise control switch. • Malfunction of the clock spring. • Malfunction of the engine-ECU. DIAGNOSIS PROCEDURE STEP 1. Check the data list. • Item 75: CANCEL switch • Item 86: cruise control ON/OFF switch • Item 91: RES + switch • Item 92: SET − switch Q: Is the check result normal? YES : Go to Step 25. NO : Go to Step 2. STEP 2. Measure the terminal voltage at cruise steering wheel with the cruise control switch ). (2) Connect the negative battery terminal that was disconnected when the driver's air bag module (3) Turn the ignition switch to the "ON" position. control switch connector terminal engine-ECU CNTS line and earth with cruise control switch OK: 4.7 − 5.0 V Q: Is the check result normal? YES : Go to Step 14. NO : Go to Step 3. STEP 3. Measure the terminal voltage at 82 81 80 79 78 77 76 75 74 73 72 71 94 93 92 91 90 89 88 87 86 85 84 83 99 98 97 96 95 100 101 102 103 104 105 106 112 113 114 109 108 107 110 111 115 116 117 118 ACB06008AB MB992110 Special tool 48-pin connector Engine-ECU (1) Connect special tool power plant ECU check harness (MB992110) between the engine-ECU (2) Turn the ignition switch to the "ON" position. tool 48-pin connector terminal No.107 OK: 4.7 − 5.0 V Q: Is the check result normal? YES : Go to Step 10. NO : Go to Step 4. STEP 4. Connector check: engine-ECU Q: Is the check result normal? YES : Go to Step 5. NO : Repair or replace the damaged connector. |