diff --git a/source/app/controllers/cfdi_xml.py b/source/app/controllers/cfdi_xml.py
index 0351477..fc5087e 100644
--- a/source/app/controllers/cfdi_xml.py
+++ b/source/app/controllers/cfdi_xml.py
@@ -139,8 +139,9 @@ class CFDI(object):
 
         return self._to_pretty_xml(ET.tostring(self._cfdi, encoding='utf-8'))
 
-    def add_sello(self, sello):
+    def add_sello(self, sello, cert_txt):
         self._cfdi.attrib['Sello'] = sello
+        self._cfdi.attrib['Certificado'] = cert_txt
         return self._to_pretty_xml(ET.tostring(self._cfdi, encoding='utf-8'))
 
     def _to_pretty_xml(self, source):
diff --git a/source/app/controllers/util.py b/source/app/controllers/util.py
index e6d4505..bbcdf90 100644
--- a/source/app/controllers/util.py
+++ b/source/app/controllers/util.py
@@ -69,10 +69,12 @@ from settings import DEBUG, MV, log, template_lookup, COMPANIES, DB_SAT, \
     PATH_XMLSEC, TEMPLATE_CANCEL, DEFAULT_SAT_PRODUCTO, DECIMALES, DIR_FACTURAS
 
 from settings import USAR_TOKEN, API, DECIMALES_TAX
-from .configpac import AUTH
+# ~ from .configpac import AUTH
 
 
 # ~ v2
+from .cfdi_cert import SATCertificate
+
 from settings import (
     EXT,
     MXN,
@@ -395,39 +397,34 @@ def to_slug(string):
     return value.replace(' ', '_')
 
 
-def make_xml(data, certificado):
-    from .cfdi_xml import CFDI
+# ~ def make_xml(data, certificado):
+    # ~ from .cfdi_xml import CFDI
 
-    token =  _get_md5(certificado.rfc)
-    # ~ if USAR_TOKEN:
-        # ~ token = auth['PASS']
-        # ~ if AUTH['DEBUG']:
-            # ~ token = AUTH['PASS']
+    # ~ cert = SATCertificate(certificado.cer, certificado.key_enc.encode())
+    # ~ if DEBUG:
+        # ~ data['emisor']['Rfc'] = certificado.rfc
+        # ~ data['emisor']['RegimenFiscal'] = '603'
 
-    if DEBUG:
-        data['emisor']['Rfc'] = certificado.rfc
-        data['emisor']['RegimenFiscal'] = '603'
+    # ~ cfdi = CFDI()
+    # ~ xml = cfdi.get_xml(data)
 
-    cfdi = CFDI()
-    xml = cfdi.get_xml(data)
+    # ~ data = {
+        # ~ 'xsltproc': PATH_XSLTPROC,
+        # ~ 'xslt': _join(PATH_XSLT, 'cadena.xslt'),
+        # ~ 'xml': save_temp(xml, 'w'),
+        # ~ 'openssl': PATH_OPENSSL,
+        # ~ 'key': save_temp(certificado.key_enc, 'w'),
+        # ~ 'pass': token,
+    # ~ }
+    # ~ args = '"{xsltproc}" "{xslt}" "{xml}" | ' \
+        # ~ '"{openssl}" dgst -sha256 -sign "{key}" -passin pass:"{pass}" | ' \
+        # ~ '"{openssl}" enc -base64 -A'.format(**data)
+    # ~ sello = _call(args)
 
-    data = {
-        'xsltproc': PATH_XSLTPROC,
-        'xslt': _join(PATH_XSLT, 'cadena.xslt'),
-        'xml': save_temp(xml, 'w'),
-        'openssl': PATH_OPENSSL,
-        'key': save_temp(certificado.key_enc, 'w'),
-        'pass': token,
-    }
-    args = '"{xsltproc}" "{xslt}" "{xml}" | ' \
-        '"{openssl}" dgst -sha256 -sign "{key}" -passin pass:"{pass}" | ' \
-        '"{openssl}" enc -base64 -A'.format(**data)
-    sello = _call(args)
+    # ~ _kill(data['xml'])
+    # ~ _kill(data['key'])
 
-    _kill(data['xml'])
-    _kill(data['key'])
-
-    return cfdi.add_sello(sello)
+    # ~ return cfdi.add_sello(sello)
 
 
 def timbra_xml(xml, auth):
diff --git a/source/app/controllers/utils.py b/source/app/controllers/utils.py
index 413df7e..5250796 100644
--- a/source/app/controllers/utils.py
+++ b/source/app/controllers/utils.py
@@ -48,6 +48,8 @@ from cryptography.hazmat.backends import default_backend
 from cryptography.hazmat.primitives import hashes
 from dateutil import parser
 
+from .cfdi_xml import CFDI
+
 from settings import DEBUG, DB_COMPANIES, PATHS
 
 from .cfdi_cert import SATCertificate
@@ -613,7 +615,7 @@ def get_client_balance(auth):
     pac = PACS[auth['pac']]()
     balance = pac.client_balance(auth)
     if pac.error:
-        balance = '-e'
+        balance = 'p/e'
 
     return balance
 
@@ -625,3 +627,20 @@ def get_cert(args):
     return cert
 
 
+def make_xml(data, certificado):
+    cert = SATCertificate(certificado.cer, certificado.key_enc.encode())
+    if DEBUG:
+        data['emisor']['Rfc'] = certificado.rfc
+        data['emisor']['RegimenFiscal'] = '603'
+
+    cfdi = CFDI()
+    xml = ET.parse(BytesIO(cfdi.get_xml(data).encode()))
+
+    path_xslt = _join(PATHS['xslt'], 'cadena.xslt')
+    xslt = open(path_xslt, 'rb')
+    transfor = ET.XSLT(ET.parse(xslt))
+    cadena = str(transfor(xml)).encode()
+    stamp = cert.sign(cadena)
+    xslt.close()
+
+    return cfdi.add_sello(stamp, cert.cer_txt)
diff --git a/source/app/models/main.py b/source/app/models/main.py
index 414e786..1a3fd71 100644
--- a/source/app/models/main.py
+++ b/source/app/models/main.py
@@ -139,21 +139,26 @@ def validar_timbrar():
 
     msg = 'Es necesario configurar un certificado de sellos'
     try:
-        obj = Certificado.select()[0]
-    except IndexError:
+        obj = Certificado.get(Certificado.es_fiel==False)
+    except Exception as e:
         return {'ok': False, 'msg': msg}
 
     if not obj.serie:
         return {'ok': False, 'msg': msg}
 
-    dias = obj.hasta - util.now()
-    if dias.days < 0:
+    diff = obj.hasta - utils.now()
+    if diff.days < 0:
         msg = 'El certificado ha vencido, es necesario cargar uno nuevo'
         return {'ok': False, 'msg': msg}
 
+    auth = Configuracion.get_({'fields': 'pac_auth'})
+    if not auth:
+        msg = 'Es necesario configurar los datos de timbrado del PAC'
+        return {'ok': False, 'msg': msg}
+
     msg = ''
-    if dias.days < 15:
-        msg = 'El certificado vence en: {} días.'.format(dias.days)
+    if diff.days < 15:
+        msg = 'El certificado vence en: {} días.'.format(diff.days)
 
     return {'ok': True, 'msg': msg}
 
@@ -1079,15 +1084,13 @@ class Emisor(BaseModel):
 
     @classmethod
     def get_timbres(cls):
-        auth = cls.get_auth()
-        if not auth:
-            return 'c/e'
+        try:
+            obj = Emisor.select()[0]
+        except IndexError:
+            return 's/e'
 
-        pac = Configuracion.get_('lst_pac').lower()
-        if pac:
-            result = utils.get_client_balance(auth, pac)
-        else:
-            result = util.get_timbres(auth)
+        auth = Configuracion.get_({'fields': 'pac_auth'})
+        result = utils.get_client_balance(auth)
         return result
 
     @classmethod
@@ -4858,7 +4861,7 @@ class Facturas(BaseModel):
             frm_vu = FORMAT_PRECIO
         tmp = 0
         emisor = Emisor.select()[0]
-        certificado = Certificado.select()[0]
+        certificado = Certificado.get(Certificado.es_fiel==False)
 
         is_edu = False
         comprobante = {}
@@ -4888,7 +4891,7 @@ class Facturas(BaseModel):
         comprobante['Fecha'] = invoice.fecha.isoformat()[:19]
         comprobante['FormaPago'] = invoice.forma_pago
         comprobante['NoCertificado'] = certificado.serie
-        comprobante['Certificado'] = certificado.cer_txt
+        # ~ comprobante['Certificado'] = certificado.cer_txt
         comprobante['SubTotal'] = FORMAT.format(invoice.subtotal)
         comprobante['Moneda'] = invoice.moneda
         comprobante['TipoCambio'] = '1'
@@ -5124,7 +5127,8 @@ class Facturas(BaseModel):
             'complementos': complementos,
         }
 
-        return util.make_xml(data, certificado)
+        # ~ return util.make_xml(data, certificado)
+        return utils.make_xml(data, certificado)
 
     @classmethod
     def get_status_sat(cls, id):
diff --git a/source/app/settings.py b/source/app/settings.py
index ed389e4..3889ee2 100644
--- a/source/app/settings.py
+++ b/source/app/settings.py
@@ -217,6 +217,7 @@ PATHS = {
     'BK': path_bk,
     'LOCAL': path_local,
     'SAT': path_sat,
+    'xslt': PATH_XSLT,
 }
 
 VALUES_PDF = {