1. As the battery, battery harness and starter motor age, cranking speeds can be greatly reduced. The most common issue (besides the battery) is the starter motor solenoid. The solenoid has a bakelite insulator where the cable poles connect, and through age and heat, the bakelite insulator becomes loose. They cannot be tightened, as they are crimped into the solenoid housing. A new solenoid/starter motor is usually required. Even after a new starter motor has been fitted, some cars still experience slow cranking speeds when the engine is warm. The main cause of this has been traced to excessive current draw from the battery harness (thanks to heat, and a once poorly operating starter). Once the battery harness has been replaced cranking speed is improved.
2. Some VT V8's (5.0ltrs) may not restart if the ignition switch has not been returned to the off position (like during a short stop where the key is not removed). Revised Memcals were introduced to eliminate this problem.
3. Some VT's that will not start, and have no fuel pressure, may have poor terminal connection on the fuel pump circuit inside the fuel sender unit assembly. A revised pump and sender unit assembly was introduced mid 2000
Gen III Pump and Sender unit assembly - Part number 25337050
Memcal VT V6 Auto - Part number 16262780 (CXWB)
Memcal VT V6 Auto LPG - Part number 16262785 (CXWJ)
Memcal VT V6 SC Auto - Part number 16262784 (CXWH)
6. Some VT's had a problem with the ignition barrel intermittently jamming in the start or on position. This may lead to starter motor failure, or a situation where the ignition cannot be turned off. There is a pin and spring within the ignition barrel that can become misaligned. This can cause the barrel to become jammed. The pin and spring are carried on from previous models, and are not required in VT's.
VT V6 Auto LPG memcal - Part number 16262785 (CXWJ)
Remote Key Readers - Some remote key readers have poor range, especially on hot days. The average working range is within 4 metres. To cope with high ambient temperatures, the remote receiver's circuit boards have been upgraded with higher tolerance capacitors from 28/08/2001.
V6 patch harness - Part number 92075373
V8 patch harness - Part number 92077126
Battery harness kit - Part number 92142111
Gauges inoperative - Some VT executives have gauge cluster "lock-up", where the tacho, speedo, gauges and some or all of the LCD readout does not work. Apparently, static electricity discharge (due to clothing or temperature) can be the cause. The top frame and cushion assembly is mounted to the seat frame with nylon bushes, which act as an insulator. An earth lead connected between the top part of the drivers seat and the base is advised.
Instrument warning lamps (ABS) - The ABS module consists of 2 main parts. A hydraulic unit and an electrical unit. The most common failure seen with the module is when the ABS Electronic module fails. This often results in a myriad of dash lights being illuminated, not just the ABS light. When the ABS Electronic module fails, it can also interrupt scanning procedures for the ABS, BCM (Body Control Module) and PCM (Powertrain Control Module).
Another cause can be water entry into the engine harness connection area, under the bonnet, against the right strut tower. Apparently, water gets onto and through the "horse-shoe" shaped plastic wiring support, which eventually tracks down to the ABS connector, causing all sorts of warning lamp issues. Foam fillers and sealants are used to help reduce the amount of water that can get through to these areas.
Indicator Switch - Some VT turn signal lamps will not work during cold temperatures. A possible cause for this can be the hazard lamp switch. If the hazard switch becomes slightly dislodged from the dash fascia, the locking tab of the hazard switch can distort the switch case. This can interrupt the signal from the indicator switch to the indicator lamps. Revised hazard switches were introduced late 1999.
Side Air Bags - In some situations, the side air bag container may distort, which can damage the airbag's electrical connector. This may eventually cause the air bag light on the dash to illuminate. Revised side air bag assemblies where introduced mid 1999.
Fuel Gauge calibration - Some early VT's will not read full on the fuel gauge, even though the tank is full. In mid 1997, the calibration was changed in production. The fuel gauge calibration can be changed by Holdens, using a Tech 2 (Holden Scan Tool).
GEN III O2 Sensors - Some Gen III Automatics will experience water contamination on the LH O2 sensor plug, which can cause O2 sensor faults. This problem may be a result of the A/C drain tube in the transmission tunnel, as it is in the same proximity as the O2 sensor harness. A bracket was introduced for the O2 sensor connector that will position it away from the A/C drain tube.
O2 Sensor Connector Mounting Kit – Part number 92145044
I have had several situations that had total failure. All doors were on deadlock, but the driver's door could be unlocked manually with the key. No other door or door lock could be opened or manipulated. After dismantling each door from the inside and removing the central locking solenoids, the doors could be opened. All the solenoids had jammed/locked into the deadlock position. All 4 solenoids where replaced. Apparently, water leaking in through the bottom of door trims, or water not draining from the doors can sometimes upset the central locking wiring and solenoids in the door.
PS; If your remote key fob breaks, don't drill a hole through it for your key ring, as the circuit board inside doesn't like it. Don't laugh, I've seen it done!