# Service bulletin 18\-073\-26

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

- Type: Service bulletin
- NHTSA id: 11035323
- Published by NHTSA: 2026\-07\-29
- Manufacturer's number: 18\-073\-26
- Manufacturer's date: 2026\-07\-22
- NHTSA component: ENGINE; POWER TRAIN

## NHTSA's summary

Flash: Powertrain Control Module \(PCM\) Updates Customers must experience a Malfunction Indicator Lamp \(MIL\) illumination and the vehicle exhibit/set SYMPTOM: one or more of the following Diagnostic Trouble Codes \(DTCs\): ● P0420 \- Catalyst System Efficiency Below Threshold Bank 1. ● P0430 \- Catalyst System Efficiency Below Threshold Bank 2. ● P0556 \- Brake Booster Pressure Sensor Circuit Performance. ● P0340 \- Cam Position Sensor Circuit \- Bank 1 Intake. ● P0345 \- Cam Position Sensor Circuit \- Bank 2 Intake. ● P0365 \- Cam Position Sensor Circuit \- Bank 1 Exhaust. ● P0390 \- Cam Position Sensor Circuit \- Bank 2 Exhaust. Customers may experience one or more of the following: ● Vehicle fails emissions inspection testing. ● Fuel odor during frequent stop and re\-start driving, during high ambient temps. In addition, the following software enhancement\(s\) is available: ● OBD calibration turned off DTC "U0463 \- Fuel Level Implausible" message code and will now be detected with DTC "P0463 \- Fuel Level Sensor 1 Circuit High". ● More robust trailer brake module enhancements for 3rd party aftermarket designs. ● Cam/crank diagnostic has been turned from a 1\-trip to a 2\-trip MIL. ● Change fuel level legislative reporting from a voltage to a percent scale. This bulletin involves reprogramming the PCM with the latest available software.

## The document

- [NHTSA's copy of the document (PDF)](https://static.nhtsa.gov/odi/tsbs/2026/MC-11035323-0001.pdf)
- [If that address does not open, try this one](https://static.nhtsa.gov/odi/tsbs/2026/MC-11035323-9999.pdf)

The document is the manufacturer's. This site does not hold it.

## Components

Engine, Transmission and driveline

## Trouble codes named

P0340, P0345, P0365, P0390, P0420, P0430, P0463, P0556, U0463

## Vehicles listed

- 2018 to 2019 RAM PROMASTER

JSON: [/v1/bulletins/11035323](/v1/bulletins/11035323)

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