Diagnostic Procedure

WARNING: This page is about a different car, the 2005 Mazda MX-5 Miata. However, it is still accessible from the selected car via links, so may be relevant.

JUDDER UPON TCC OPERATION - DIAGNOSTIC PROCEDURE

STEP	INSPECTION		ACTION
1	Inspect for abnormal signal change at the following TCM terminals when judder occurs: Throttle position sensor signal (TCM terminal U) Output speed sensor signal (TCM terminals AE and AF) Input/turbine speed sensor signal (TCM terminals W and Z) Are all signals okay?	Yes	Go to next step.
1		No	Inspect related wiring harness and sensor for intermittent open or short circuit.
2	Connect WDS or equivalent to data link connector-2. Access VSS and TP PIDs. Inspect TCM terminal AO voltage in TCC operating condition while monitoring VSS and TP PIDs. (See TRANSMISSION CONTROL MODULE (TCM) INSPECTION ) Specification: B+ in TCC condition Does voltage change from 0 V to B+ with correct TCC timing?	Yes	Inspect for continuity between TCM terminal AO and TCC solenoid valve terminal C. Inspect if TCC solenoid valve is stuck. (See SOLENOID VALVES INSPECTION . ) If okay, go to next step.
2		No	Inspect TCM terminal for bending, damage, corrosion, or loose connection. Inspect for short to ground between TCC solenoid valve terminal C and TCM terminal AO.
3	Overhaul control valve body and repair or replace any defective parts. Is problem eliminated?	Yes	AT is now normal.
3		No	Replace torque converter.
4	Verify test results. If okay, return to diagnostic index to service any additional symptoms. If malfunction remains, inspect related Service Bulletins and/or On-line Repair Information and perform repair or diagnosis. If vehicle is repaired, troubleshooting completed. If vehicle is not repaired or additional diagnostic information is not available, replace TCM.