[Moto G4 Plus Questions & Answers] gghose:
My XT1625 was acting up so badly I couldn't even do a factory reset within the OS (which had been upgraded to the April security fix). Note this is the Amazon version and the bootloader is locked.

I'm trying to flash ATHENE_AMZ_NPJ25.93-14.7_cid50_subsidy-DEFAULT_regulatory-DEFAULT_CFC

and I get messages like:

fastboot flash partition gpt.bin

(bootloader) slot-count: not found

(bootloader) slot-suffixes: not found

(bootloader) slot-suffixes: not found

(bootloader) has-slot:partition: not found

target reported max download size of 536870912 bytes

sending 'partition' (32 KB)...

OKAY [ 0.004s]

writing 'partition'...

(bootloader) Security version downgrade

(bootloader) Image primary_gpt failed validation

(bootloader) Preflash validation failed

FAILED (remote failure)

finished. total time: 0.042s

fastboot getvar all reports:

(bootloader) slot-count: not found

(bootloader) slot-suffixes: not found

(bootloader) slot-suffixes: not found

(bootloader) version: 0.5

(bootloader) version-bootloader: moto-msm8952-B1.06

(bootloader) product: athene_13mp

(bootloader) board: athene_13mp

(bootloader) secure: yes

(bootloader) hwrev: P2A

(bootloader) radio: 1

(bootloader) storage-type: emmc

(bootloader) emmc: 16GB SAMSUNG QE13MB RV=08 PV=07 FV=0000000000000007

(bootloader) ram: 2GB SAMSUNG LP3 DIE=8Gb M5=01 M6=05 M7=00 M8=1F

(bootloader) cpu: MSM8952

(bootloader) serialno: ZY223CCCVK

(bootloader) cid: 0x0032

(bootloader) channelid: 0x93

(bootloader) uid: E9940E0100000000000000000000

(bootloader) securestate: oem_locked

(bootloader) iswarrantyvoid: no

(bootloader) max-download-size: 536870912

(bootloader) reason: Reboot mode set to fastboot

(bootloader) imei: 354124070776679

(bootloader) meid:

(bootloader) date: 06-22-2016

(bootloader) sku: XT1625

(bootloader) battid: SNN5966A

(bootloader) iccid:

(bootloader) cust_md5:

(bootloader) max-sparse-size: 268435456

(bootloader) current-time: "Sun Oct 2 7:17:53 UTC 2016"

(bootloader) ro.build.fingerprint[0]: motorola/athene_amz/athene:7.0/NPJ

(bootloader) ro.build.fingerprint[1]: S25.93-14-18/6:user/release-keys

(bootloader) ro.build.version.full[0]: Blur_Version.25.236.6.athene_amz.

(bootloader) ro.build.version.full[1]: amz.en.US

(bootloader) ro.build.version.qcom: LA.BR.1.3.6-01710-8976.0

(bootloader) version-baseband[0]: M8952_70030.25.03.62.02R ATHENE_RETUSA

(bootloader) version-baseband[1]: _CUST

(bootloader) kernel.version[0]: Linux version 3.10.84-ge03508d-00131-g44

(bootloader) kernel.version[1]: 2576f (hudsoncm@ilclbld72) (gcc version

(bootloader) kernel.version[2]: 4.8 (GCC) ) #1 SMP PREEMPT Wed Mar 28 06

(bootloader) kernel.version[3]: :58:16 CDT 2018

(bootloader) sbl1.git: git=MBM-NG-VB1.06-0-g57d1343

(bootloader) rpm.git: git=MBM-NG-VB1.06-0-ga970ead

(bootloader) tz.git: git=69dd24b-dirty

(bootloader) hyp.git: git=69dd24b-dirty

(bootloader) keymaster.git: git=69dd24b-dirty

(bootloader) cmnlib.git: git=69dd24b-dirty

(bootloader) aboot.git: git=MBM-NG-VB1.06-0-g0edfb0d

(bootloader) qe: qe 0/0

(bootloader) frp-state: protected (77)

(bootloader) ro.carrier: amz

all: listed above

finished. total time: 0.082s

Any suggestions? I called up Motorola and they want $125 for a replacement, which hardly seems worth it given the age of the phone.