diff --git a/src/main.cpp b/src/main.cpp
index 28738ab..dcbaf46 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -441,6 +441,10 @@ static bool send_inflight_batch(uint32_t ts_for_display) {
   input.dt_s = dt_s > 0 ? static_cast<uint8_t>(dt_s) : 1;
   input.n = g_inflight_count;
   input.battery_mV = battery_mv_from_voltage(g_inflight_samples[g_inflight_count - 1].battery_voltage_v);
+  input.err_m = g_sender_faults.meter_read_fail > 255 ? 255 : static_cast<uint8_t>(g_sender_faults.meter_read_fail);
+  input.err_d = g_sender_faults.decode_fail > 255 ? 255 : static_cast<uint8_t>(g_sender_faults.decode_fail);
+  input.err_tx = g_sender_faults.lora_tx_fail > 255 ? 255 : static_cast<uint8_t>(g_sender_faults.lora_tx_fail);
+  input.err_last = static_cast<uint8_t>(g_sender_last_error);
   for (uint8_t i = 0; i < g_inflight_count; ++i) {
     input.energy_wh[i] = kwh_to_wh_from_float(g_inflight_samples[i].energy_total_kwh);
     if (!float_to_i16_w(g_inflight_samples[i].phase_power_w[0], input.p1_w[i]) ||
@@ -889,10 +893,10 @@ static void receiver_loop() {
             data.link_valid = true;
             data.link_rssi_dbm = pkt.rssi_dbm;
             data.link_snr_db = pkt.snr_db;
-            data.err_meter_read = 0;
-            data.err_decode = 0;
-            data.err_lora_tx = 0;
-            data.last_error = FaultType::None;
+            data.err_meter_read = batch.err_m;
+            data.err_decode = batch.err_d;
+            data.err_lora_tx = batch.err_tx;
+            data.last_error = static_cast<FaultType>(batch.err_last);
           }
 
           if (sender_idx >= 0) {
diff --git a/src/payload_codec.cpp b/src/payload_codec.cpp
index f962b3b..7781f78 100644
--- a/src/payload_codec.cpp
+++ b/src/payload_codec.cpp
@@ -108,7 +108,7 @@ bool encode_batch(const BatchInput &in, uint8_t *out, size_t out_cap, size_t *ou
     return false;
   }
   size_t pos = 0;
-  if (!ensure_capacity(16, out_cap, pos)) {
+  if (!ensure_capacity(20, out_cap, pos)) {
     return false;
   }
   write_u16_le(&out[pos], kMagic);
@@ -125,6 +125,10 @@ bool encode_batch(const BatchInput &in, uint8_t *out, size_t out_cap, size_t *ou
   out[pos++] = in.n;
   write_u16_le(&out[pos], in.battery_mV);
   pos += 2;
+  out[pos++] = in.err_m;
+  out[pos++] = in.err_d;
+  out[pos++] = in.err_tx;
+  out[pos++] = in.err_last;
 
   if (!ensure_capacity(4, out_cap, pos)) {
     return false;
@@ -179,7 +183,7 @@ bool decode_batch(const uint8_t *buf, size_t len, BatchInput *out) {
     return false;
   }
   size_t pos = 0;
-  if (len < 16) {
+  if (len < 20) {
     return false;
   }
   uint16_t magic = read_u16_le(&buf[pos]);
@@ -199,6 +203,10 @@ bool decode_batch(const uint8_t *buf, size_t len, BatchInput *out) {
   out->n = buf[pos++];
   out->battery_mV = read_u16_le(&buf[pos]);
   pos += 2;
+  out->err_m = buf[pos++];
+  out->err_d = buf[pos++];
+  out->err_tx = buf[pos++];
+  out->err_last = buf[pos++];
 
   if (out->n == 0 || out->n > kMaxSamples || out->dt_s == 0) {
     return false;
@@ -271,6 +279,10 @@ bool payload_codec_self_test() {
   in.dt_s = 1;
   in.n = 5;
   in.battery_mV = 3750;
+  in.err_m = 2;
+  in.err_d = 1;
+  in.err_tx = 3;
+  in.err_last = 2;
   in.energy_wh[0] = 100000;
   in.energy_wh[1] = 100001;
   in.energy_wh[2] = 100050;
@@ -306,7 +318,8 @@ bool payload_codec_self_test() {
   }
 
   if (out.sender_id != in.sender_id || out.batch_id != in.batch_id || out.t_last != in.t_last ||
-      out.dt_s != in.dt_s || out.n != in.n || out.battery_mV != in.battery_mV) {
+      out.dt_s != in.dt_s || out.n != in.n || out.battery_mV != in.battery_mV ||
+      out.err_m != in.err_m || out.err_d != in.err_d || out.err_tx != in.err_tx || out.err_last != in.err_last) {
     Serial.println("payload_codec_self_test: header mismatch");
     return false;
   }
diff --git a/src/payload_codec.h b/src/payload_codec.h
index 1098089..36f388e 100644
--- a/src/payload_codec.h
+++ b/src/payload_codec.h
@@ -9,6 +9,10 @@ struct BatchInput {
   uint8_t dt_s;
   uint8_t n;
   uint16_t battery_mV;
+  uint8_t err_m;
+  uint8_t err_d;
+  uint8_t err_tx;
+  uint8_t err_last;
   uint32_t energy_wh[30];
   int16_t p1_w[30];
   int16_t p2_w[30];