Service bulletin NTB21-002

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.

The communication, as NHTSA indexes it (as of 2026-10-19)
Type	Service bulletin
NHTSA id	10186849
Published by NHTSA	2021-02-06
Manufacturer's number	NTB21-002
Manufacturer's date	2021-01-06
NHTSA component	ENGINE AND ENGINE COOLING

NHTSA's summary

2020 FRONTIER; TCM COMMUNICATION ERROR CAUSING A NO START CONDITION IF YOU CONFIRM The customer states the engine will not crank and will not start. (The incident may be intermittent.) And There is a U0101 DTC (Lost Comm TCM) in the Engine Control Unit (ECU) and/or Shifter Control Unit (SCU). This DTC may be in a PAST or CURRENT status. Or The TCM shows “UNKWN” in the PRESENT column or “0” in the PAST column under the CAN DIAG SUPPORT MNTR tab within the ECU (ENGINE) or the SCU (SHIFT) in CONSULT-III plus (C-III plus). See Figure 1 and Figure 2.

The document

The document is the manufacturer's. This site does not hold it. NHTSA files a document at one of these two addresses; we have not asked NHTSA which.

Components

Engine

Trouble codes named

U0101

Vehicles listed
NISSAN FRONTIER	2020

Listing a model year does not mean every vehicle of it is concerned: the document says which.

Other bulletins for the same vehicles and component
NTB21-002A	2022-10-14. Service bulletin. TCM COMMUNICATION ERROR CAUSING A NO START CONDITION SERVICE INFORMATION If a customer states the engine will not crank and will not start (may be intermittent) and DTC U0101 (Lost Comm TCM) is stored in the ECU (ENGINE), and/or stored in the SCU (SHIFT) as PAST or CURRENT, OR The TCM shows as “UNKWN” in the PRESENT column, or “0” in the PAST column, under the CAN DIAG SUPPORT MNTR tab in the ECU or SCU in C-III plus. • Please check Service COMM or Dealer Business Systems (DBS) National Service History to confirm if campaign R22B1 or R22A9 has been applied. 1. Has campaign R22B1 or R22A9 already been completed? No: Complete the related campaign bulletin. Yes: Proceed to step 2. 2. Refer to the ESM for further diagnostic information not covered by this bulletin. NOTE: If the Park indicator is not displayed in the Driver Information Center (Figure 1) and C-III plus does not display the current TCM part number after a 2 minute wait with the ignition ON, engine OFF, this TSB does not apply. Refer to the ESM for further diagnostic information. This bulletin has been amended. See AMENDMENT HISTORY on the last page. Please discard previous versions of this bulletin.
NTB22-026	2022-06-08. Service bulletin. SERVICE INFORMATION FOR FUEL GAUGE INACCURATE WITH DTCS STORED IN ECM SERVICE INFORMATION If a fuel level sensor has been diagnosed as sending an incorrect level signal, and one or more of the following DTCs are stored in the ECM, do not replace the entire “Fuel Level Sensor Unit, Fuel Filter and Fuel Pump Assembly” (fuel pump assembly). The fuel level sensor can be replaced separately. • P0460 (FUEL LEV SEN SLOSH) • P0461 (FUEL LEVEL SENSOR) • P0462 (FUEL LEVL SEN/CIRC) • P0463 (FUEL LEVL SEN/CIRC) NOTE: Warranty claims referring to fuel level issues that result in the replacement of the entire fuel pump assembly will be charged back.
NTB17-082E	2022-03-12. Service bulletin. DTC P0456 CAUSED BY EVAP LEAK AT VENT CONTROL VALVE O-RING This bulletin has been amended. See AMENDMENT HISTORY on the last page. Please discard previous versions of this bulletin.
NTB13-097J	2022-03-12. Service bulletin. EVAP LEAK DTC P0442, P0455, P0456 INFORMATION This bulletin has been amended. See AMENDMENT HISTORY on the last page. Please discard previous versions of this bulletin.
NTB13-027C	2022-03-12. Service bulletin. CAN COMMUNICATION – NETWORK DIAGNOSTIC FLOW CHART This bulletin has been amended. See AMENDMENT HISTORY on the last page. Please discard previous versions of this bulletin.
NTB21-080	2021-10-16. Service bulletin. MIL ON WITH DTC P0223, P0507 AND/OR P2135 STORED IN THE ECM IF YOU CONFIRM The MIL is ON and one or more of the following DTCs is stored in the ECM: • P0223 - TP SEN 1/CIRC-B1 • P0507 - ISC SYSTEM • P2135 - TP SENSOR-B1 AND There are no drivability concerns. ACTION 1. Confirm the current ECM part number. 2. Reprogram the ECM, if applicable.
NTB21-073	2021-09-10. Service bulletin. HESITATION AND/OR SHIFT SHOCK IF YOU CONFIRM The customer reports hesitation and/or shift shock during acceleration, OR Shift shock during deceleration, AND There are no TCM related DTCs stored. ACTION 1. Confirm the current TCM part number. 2. Reprogram the TCM, if applicable.
NTB21-027	2021-05-08. Service bulletin. MIL ON WITH DTC P062F AND/OR P0603 STORED IF YOU CONFIRM The MIL is ON and DTC P062F (EEPROM) and/or P0603 (ECM BACK UP/CIRCUIT) is stored, And The customer stated the vehicle was recently started after sitting for an extended period of time (i.e., the battery voltage was low while attempting to start the engine). ACTION 1. Test the vehicle’s 12 volt battery using the Midtronics DSS-5000. Recharge or replace the battery if necessary. 2. Erase all DTCs.