Protege & Protege5
WARNING: This page is about a different car, the 2003 Mazda Protege5, 2003 Mazda Protege, 2003 Mazda MX-5 Miata, 2003 Mazda MPV, and 2003 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.
- Visual Inspection
Remove Vehicle Speed Sensor (VSS). Clean off any particles or metal shavings from sensor. Reinstall VSS. - Wave Profile Inspection
Remove PCM. Connect 104-Pin Breakout Box (49-UN01-130) to PCM harness connector and PCM. See Figure. Connect scan tool to DLC-2. Connect oscilloscope test leads to following breakout box terminals:- Positive test lead - breakout box terminal No. 58.
- Negative test lead - breakout box terminal No. 103.
Start engine. Monitor VSS PID. With oscilloscope settings at 1 V/DIV (Y), 2.5 ms/DIV (X), DC range, inspect wave profile. See Fig 1. If wave profile or voltage are out of specification, go to next step.
- Power Supply Voltage Inspection
Disconnect VSS 3-pin harness connector. Turn ignition on. Measure voltage at VSS 3-pin harness connector terminal "B" (Violet/Red wire). VSS voltage reading should be 4.5-5.5 volts. If VSS voltage reading is not as specified, go to next step. - Open/Short Circuit Inspection
Disconnect PCM 104-pin harness connector and VSS 3-pin harness connector. Using ohmmeter, check following circuits:- Power circuit - check for short or open circuit in White/Red wire between VSS 3-pin harness connector terminal "A" and main relay 4-pin harness connector terminal "D".
- Ground circuit - check for open circuit in Black/Orange wire between VSS 3-pin harness connector terminal "C" and ground.
If open/short circuit is present, repair short or open circuit in appropriate wire or replace wire harness as necessary. If open/short circuit is not present, go to next step.
- Sensor Rotor Inspection
Remove VSS. Shift selector lever to "N" position. Inspect sensor rotor surface through hole for VSS while rotating front wheel by hand. Ensure sensor rotor surface does not have metal particles or shavings and is not cracked or damaged. Clean or replace sensor rotor as necessary. If sensor rotor is okay, replace VSS.