Powertrain, generic (extended)

P2470 Exhaust Gas Temperature Sensor Circuit Low (Bank 1 Sensor 4)

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modeNo

P2470 means the signal of bank 1 probe number 4 has dropped below its valid floor, which on resistive probes indicates a short to ground. Ford's diesels flag a voltage under 0.10 V with the key on and 9 to 16.25 V supply, checked continuously over about 2 s. GM's diesel tables check whether the probe output stage is grounded: below 158 Ω in the 2017 and 2020 tables, below 500 Ω in 2018, and in the 2025 tables below 1 Ω or a digital reading under −72.8 °C after 19 of 25 samples, each time as a Type B fault. Ram lists P2470 for 2025–2026 Ram 2500/3500 in case S2625000003, which asks to check battery voltage before any exhaust sensor diagnosis. Chafed wiring at the exhaust and a shorted probe are the usual finds. Too high or open is P2471.

Likely causes

Signal wire chafed through and touching ground
Internal short inside the probe
Low battery voltage during diagnosis distorting readings (Ram)

Symptoms

  • MIL on
  • Implausible value for the last exhaust probe
  • Regeneration or DEF dosing inhibited

Repair estimate

DifficultyMediumDIY possible
Parts and labour€20–350
Time0.3–1.5 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

egt sensor b1s4egt wiring

Related codes

P2471P2472P246EP246FP242CP2475

References: fordservicecontent.com, gsi.ext.gm.com, gsi.ext.gm.com, gsi.ext.gm.com.