Engine Controls - Master/Hybrid MIL ON/DTC P3125
ENGINEEG021-02
November 20, 2002
Title:
MASTER, HYBRID & M.I.L. "ON" P3125 INFORMATION CODE 287
Models:
'01-'02 Prius
Introduction
Under certain driving conditions, some Prius vehicles may exhibit a Master, Hybrid and M.I.L. Warning Lights "ON" condition where DTC P3125, information code 287 ONLY has set in the Hybrid Vehicle Control Unit (HV ECU). Use the following procedure to identify whether the HV ECU or inverter/converter assembly should be replaced.
NOTE:
The HV ECU Is to be replaced ONLY if the recorded information code 287 data satisfies ALL of the following 3 conditions:
^ Vehicle speed is between 25 - 44 mph.
^ Throttle opening Is 60% or more.
^ Vehicle indicated speed is greater than the recorded MG2 revolutions. If 1 or more of the above conditions DO NOT apply, use the Prius Repair Manual P3125, information code 287 Fault Isolation Procedure (FIP).
Applicable Vehicles
^ 2001 - 2002 model year Prius vehicles produced BEFORE the Production Change Effective VIN shown below.
Production Change Effective
Parts Information
Warranty Information
Applicable Warranty *
This repair is covered under the Toyota Hybrid Vehicle System Warranty. This warranty is in effect for 96 months or 100,000 miles, whichever occurs first, from the vehicle's in-service date.
* Warranty application is limited to correction of a problem based upon a customer's specific complaint.
Required Tools & Material
NOTE:
Additional Diagnostic Tester Kits, Program Cards or SSTs may be ordered by calling SPX/OTC at 1-800-933-8335.
Diagnostic Procedure
Repair Procedure
A. Removal and Replacement of HV ECU.
Please refer to Figure 6 and the following instructions to remove and replace the HV ECU:
1. Turn the ignition key on, push the radio power button and the audio button. Record the radio presets. Turn off all lights and accessories.
2. Turn ignition key off and remove the key.
3. Remove the auxiliary battery cover.
4. Disconnect the negative (-) terminal from the auxiliary battery. To prevent damage to the battery terminal, loosen the cable nut and raise the terminal straight up without twisting or prying the cable.
5. Remove the R/F door scuff plate and cowl side trim (see Figure 6).
6. Fold the carpet back towards the passenger seat.
7. Unbolt and remove the ECU Bracket (See Figure 6).
8. Unbolt and remove the HV ECU. Carefully remove the wire harness protector and unplug the electrical connectors from the HV ECU. Peel the (plastic) ECU Cover off the HV ECU (See Figure 6).
9. Unscrew and remove the HV ECU mounting brackets.
10. Screw the mounting brackets onto the new HV ECU. Install the (plastic) ECU Cover.
11. Carefully plug each electrical connector and install the wire harness protector.
12. Install the HV ECU and torque the mounting nuts.
Torque: 52 in.lbf (6.0 N.m, 60 kgf.cm).
13. Install the ECU Bracket. Torque the mounting bolts and nuts.
Torque: 52 in.lbf (6.0 N.m, 60 kgf.cm).
14. Roll out the carpet and install the front door scuff plate and cowl side trim.
15. Connect the negative (-) battery terminal and tighten the cable nut.
Torque: 52 in.lbf (6.0 N.m, 60 kgf.cm).
16. Remove the positive (+) battery terminal cover.
17. Connect the 12 volt Prius Automatic Trickle Charger SST (P/N 00002-YA122-01) to the auxiliary battery. Red charger clamp to the positive (+) terminal and the black charger clamp to the negative (-) battery terminal.
18. Plug the charger into a grounded 110V nominal outlet and verify the red "POWER" light is on. Push the charger current toggle switch to the 10 amp position. Ensure the yellow "CHARGING" light is on.
B. HV Immobilizer Key Code Registration Procedure.
1. Ensure the parking brake is applied and the running mode selector lever is in "P."
2. Insert the ignition key and turn the ignition switch to the "ON" position. Leave the vehicle in this condition for at least 30 minutes.
3. After a minimum of 30 minutes has elapsed, turn the ignition key "OFF."
4. Unplug the charger from the 11OV outlet. Remove the red and black charger clamps from the battery.
5. Install the battery positive (+) terminal cover.
6. Install the auxiliary battery cover.
7. Depress the brake pedal, turn and hold the ignition switch to "START" until the green "READY" indicator light remains on and steady. Then release the ignition key.
8. Ensure no trouble lights are illuminated on the Instrument panel or Multi-Information Display (MID).
9. Reset all recorded radio stations. Turn the power on, press "AUDIO." Tune to desired station, press and hold until a beep is heard. Repeat for each station, FM1, FM2, and AM.
10. Reset the clock to the current time.