India A won the first four day match by an innings and 30 runs.
Starting the final day on 294 for 7, the Proteas added 25 runs losing the remaining three wickets to get all out for 319 in 98.2 overs.
Mohammed Siraj (4/72) and Ankit Rajpoot (3/52) shared bulk of the spoils while limited overs specialist Yuzvendra Chahal grabbed two for 84 in 22 overs.
With a slender 26-run lead, India A finished their second essay at 181 for 4 with Iyer (65) and Bawne (64 no) steadying the ship with a 86-run stand for the fourth wicket.
Iyer hit four boundaries and four sixes in 103 balls while Bawne hit nine boundaries in 100 deliveries.
This was after Prithvi Shaw (4) and Mayank Agarwal (28) were dismissed cheaply.
"I am happy that I got some runs under my belt. For sure, there was nothing wrong in my batting in the last two innings, just that I needed to convert 30s into big scores, which I tried focussing on," Iyer told reporters at post-match press conference.
The match was called off at tea after heavens opened up.
Brief Score: India A first innings: 345 all out in 101 Overs (GH Vihari 148; D Olivier 6/63)
South Africa A first innings: 319 all out in 98.2 Overs (Zubayr Hamza 93, SJ Erwee 58; Mohammad Siraj 4/72; Ankit Rajpoot 3/52; YS Chahal 2/84)
India A 2nd innings: 181 for 4 in 51 overs (Shreyas Iyer 65; Ankit Bawne 65 not out; Duanne Olivier 2/24; Seuran Muthusamy 2/45).
First Published: August 13, 2018, 7:21 PM IST