Hilux preheating lamp stays on

Greetings! I am writing to inform you that I encountered an almost identical predicament in my Hilux. The symptoms you have delineated bear a striking resemblance to those I previously confronted. May I inquire whether you have scrutinized the integrity of the wiring harness that interfaces with the preheating control unit? It is conceivable that corrosion or damage to the insulation could precipitate the observed malfunctions. What is the state of the battery?

Thanks for chiming in! Wiring harness... hmm, I gave it a cursory glance, but didn't go full CSI on it. What exactly should I be looking for – any specific wires prone to problems, or areas where they tend to rub and fray?

With respect, discerning the precise location of potential vulnerabilities within the wiring harness can prove challenging without employing specialized diagnostic apparatus. In my particular case, the source of the malfunction remained elusive until a qualified technician, equipped with advanced analytical tools, was able to pinpoint the anomaly. Therefore, I respectfully suggest consulting with a reputable automotive service center possessing expertise in Toyota vehicles. Attempting to effect repairs independently, absent the requisite knowledge and resources, may inadvertently exacerbate the situation and potentially engender supplementary complications. Based on my experience, I would estimate a financial outlay in the realm of 95€

Roger that, thanks a million! Sounds like a trip to the shop is in order. Turns out you were spot on - it was indeed a faulty cable connection to the preheating control unit, and it was sorted out without costing me an arm and a leg.