2003-2004 MAZDA6 3.0L - MIL ILLUMINATION WITH DTC P2135 OR DTCs P0123 AND/OR P0222 AFTER THROTTLE BODY REPLACEMENT
APPLICABLE MODEL(S)/VINS 2003-2004 Mazda6 3.0L
Some vehicles may experience a MIL illumination with DTC P2135 stored in memory or DTCs P0123 and/or P0222 after the
throttle body has been replaced.
* DTC P2135: Throttle Position Sensor No.1 / No. 2 Voltage Correlation
* DTC P0123: Throttle Position Sensor No.1 Circuit High Input
* DTC P0222: Throttle Position Sensor No.2 Circuit Low Input
DTCs P0123 and/or P0222 may be stored immediately (or some time later) after installing a new throttle body with either
part number AJ57-13-640D or AJT1-13-640. This is due to an abnormal electrical noise within the engine harness of certain
vehicles. This condition can be prevented or corrected by installing the throttle body harness (with diode) as described
in this service bulletin.
NOTE: The throttle body harness (with diode) should only be used to correct DTCs P0123 and/or P0222 that were set AFTER
the throttle body was replaced. Vehicles that have stored DTCs P0123 and/or P0222 without a throttle body replacement
should be diagnosed and repaired according to the workshop manual, not this service bulletin.
1. Verify customer concern.
2. Determine which DTC(s) are present.
* If DTCs P0123 and/or P0222 are present (AFTER throttle body replacement), install throttle body harness/diode
(AJT1-13-ZS8) according to "Throttle Body Harness (with Diode) Installation Procedure" below.
* If DTC P2135 is present, replace the throttle body with a new part (AJ57-13-640) according to the online
instructions on MS3 or Workshop Manual (section 01-13 INTAKE AIR SYSTEM REMOVAL/INSTALLATION (AJ)), then
install a throttle body harness/diode (AJT1-13-ZS8) according to "Throttle Body Harness (with Diode)
Installation Procedure" below.
Throttle Body Harness (with Diode) Installation Procedure:
1. Record the customer's preset radio stations.
2. Disconnect the negative battery cable.
3. Disconnect connector from the throttle body.
4. Disconnect the harness retainer from the intake manifold.
5. Remove the terminal lock from the connector.
6. Remove all six (6) terminals from the original connector using an appropriate terminal tool (A) as shown below.
* This is necessary to install the new connector with the pre-installed diode.
* Angle of the tool goes upward to release the terminal lock.
* Discard original connector.
7. Re-insert W, GY, G/R, and B/O female terminals into connector.
ETB Connector B2-25 Wiring Locations:
Location Wire Color
#1 White (W)
#2 Brown (BR) *
#3 Yellow (Y) *
#4 Gray (GY)
#5 Green/Red (G/R)
#6 Black/Orange (B/O)
* - Pre-installed wires
8. Re-install the red terminal lock onto the connector.
9. Place the heat shrink (A) over both Yellow (B) and Brown (C) female terminals.
10. Connect the Yellow female terminal (from vehicle harness) and male terminal (D) (from new connector). Repeat
for the Brown female and male terminal (E).
11. Solder the joints together.
* Before soldering, make sure the soldering iron is fully warmed up and its edge is cleaned with a sponge
or rag soaked in water.
* Be careful not to melt the heat shrink tube while soldering.
* To prevent the heat shrink tube from shrinking due to heat generated during soldering, the heat shrink
tube must be kept away from the heat generated at the soldering spot.
12. Using suitable pliers, squeeze both the Yellow and Brown female terminals at the protrusion to prevent sharp
edges protruding through the heat shrink tubing.
13. Place heat shrink (A) over both solder joints and shrink using a heat gun (B).
NOTE: Warm the wire up until plastic comes out from the edge, but do not touch the plastic right after shrinkage
when it is soft.
14. Fold the wires so they are flush with the harness.
15. Install the corrugated tube.
NOTE: Be sure the harness fastener can be seen after installing the tube.
16. Secure the tube with electrical tape.
17. Reconnect the harness to the electronic throttle body.
18. Connect the negative battery cable.
19. Re-enter the customer's preset radio stations.
20. Verify repair.
NOTE: Order the correct part numbers based on the DTC(s) stored in memory.
** Please confirm most recent TSB information directly from Mazda