Follow-up to Toyota computer problem, post 4379

Our intermittent engine ‘Malfunction’ warning light that kills grunt,has been solved.

The intermittent fault was kind to us and allowed us to travel over the big hills fault-free to Hobart.

We put Tojo in for 100,000km service on Friday, plus to try to find the warning light problem. From the computer fault log, they were able to indicate the problem region, as being the area of the throttle control motor, but did not locate the source of the fault.
However after the service, the intermittent problem became a permanent problem every time Tojo was started. The computer puts the engine into “get-you-home” mode, & limits Tojo to 80kph on level travel without a BT behind.

Since the Tojo service centre was going to be closed for the long weekend, I decided to have an uneducated look under the bonnet (I’m an old electronic engineer, not a motor mechanic). Anyhow in the region of the throttle control motor, I bumped a wire on the plug for the throttle position switch, which fell off.

The fault was caused by the broken wire making an intermittent break that signaled the computer of a fault condition. This plug is in a ‘hot’ position, & the insulation on the wires had hardened & stiffened, & the wires had broken inside the insulation, & were making intermittent contact.

Have made some temporary repairs until we get home ----phew!!

Neil