Fault Codes/Caterpillar Inc./27/59Caterpillar Inc.27/59UnclassifiedElectricalWhat This Code MeansGenerator over/under voltageRelated Caterpillar Inc. Fault Codes3232/32RV32RV4650/5181 O/U10001052-0401063-0401064-5711078-0111078-535Browse all Caterpillar Inc. fault codes→ASK RUDY ABOUT THIS FAULTGet a diagnosis walkthrough for 27/59 on your specific Caterpillar Inc. unit — cited to the OEM manual, not a forum guess.Your question about 27/59GET THE ANSWERFree account required — we'll bring your question with you.